Laurisilva
Encyclopedia
Laurisilva or laurissilva ("laurel forest
") is a subtropical forest
, found in areas with high humidity and relatively stable and mild temperatures. They are characterised by evergreen, glossy-leaved tree species that look alike with leaves of lauroide type. The members of the Laurel family (Lauraceae
) could be prominent, or in association.
Of particular note is the endemic
type of humid subtropical laurel forest
, macaronesian laurisilva, found on several of the Macaronesia
n islands of the North Atlantic and Macaronesian African mainland enclaves, namely Madeira Islands, the Azores
, Cape Verde
Islands and the Canary Islands
, a relict
of the Pliocene
subtropical forest
s, supporting numerous endemic species.
In Spanish
, the word "laurisilva" is used for every laurel forest: Laurisilva misionera, laurisilva valdiviana, etc.
in the eastern Atlantic, in particular the Azores
, Madeira Islands, and western Canary Islands
, from 400 m to 1200 m elevation. Trees of the genera Apollonias
(Lauraceae
), Ocotea
(Lauraceae), Persea
(Lauraceae), Clethra
(Clethraceae), Dracaena
(Ruscaceae
), and Picconia
(Oleaceae
) are characteristic. The Madeira Islands laurel forest was designated a World Heritage Site
by UNESCO
in 1999.
The forests are made up of laurel-leaved evergreen
hardwood
tree
s, reaching up to 40 m in height. Many of the species
are endemic
to the islands, and harbour a rich biota
of understorey plants, invertebrate
s, and bird
s and bat
s.
Laurisilva formerly covered much of the mountain areas of Annobon
, Azores, Bioko
, Cape Verde
, Canary Islands, Madeira, São Tomé
, Príncipe
, other Atlantic islands, and locally on favourable wet climate microenvironments of the coast and coastal mountains of the north-west African mainland, but the forests have been much reduced in extent by logging
, clearance for agriculture
and grazing
, and the invasion of exotic species. The most extensive laurisilva forests remain on Madeira, where they are found between 300 m and 1400 m altitude on the northern slope, and 700 m to 1600 m on the southern slope, and cover 149,5 km². In the Canary Islands, roughly 60 km² of laurisilva remain on Tenerife
, smaller areas on La Palma
, over 20 km² in Garajonay National Park
on La Gomera
, and relict areas in Gran Canaria
. In the Azores, small patches of laurisilva forest remain on the islands of Pico
, Terceira
, and São Miguel
.
The Madeira laurisilva forests, the largest remaining stands, were declared a UNESCO
World Heritage Site
in 1999. Predominant lauraceous
trees include Til (Ocotea foetens
), Loureiro (Laurus novocanariensis
), Vinhático (Persea indica
), a valuable hardwood, and Barbosano (Apollonias barbujana); other important trees include Aderno (Heberdenia excelsa
), Pau Branco (Picconia excelsa
), the Mocanos (Visnea mocanera
and Pittosporum coriaceum
), and Sanguinho (Rhamnus glandulosa
), and the small trees or large shrubs Folhado (Clethra arborea
) and Perado (Ilex perado). The forests support a diverse understorey of fern
s and bryophyte
s, which both require moisture for reproduction, evergreen
climbing plants like Canarina canariensis, asparagus species
and Araliaceae
s (Hedera helix
, Hedera canariensis
) and of herbaceous plants
, including the Leitugas (Sonchus
spp.), geraniums (Geranium maderense, G. palmatum and G. rubescens), the Estreleiras (Argyranthemum
spp.) and the endemic orchid Goodyera macrophylla.
Lanzarote and Fuerteventura are very close to the African mainland (96 km), and were even closer during the Ice Age
of the Quaternary
(18,000 years ago, roughly 60 km). The vegetation is very similar to the basement floor of the eastern Canary Islands. A large number of plant species and some animals are common, mainly arthropod
s, but the most unusual given that many of these taxon
are endemic to both regions, the insular and continental. Often displayed species vicarious
within a gender which, in turn, is endemic in both regions: Lotus marocanus / Lotus glaucus; Bubonium intrincatum / Bubonium sericeum; Euphorbia echinus y Euphorbia beaumieriana / Euphorbia handiensis; Kleinia anteuphorbium / Kleinia neriifolia; Lavandula maroccana / Lavandula multifida
; Sonchus leptocephalus / Warionia saharae.
The phytosociology
of these configurations was described in a paper by Rivas Goday and Esteve Chueca.
A large relict population of the drago
plant (Dracaena
) was recently discovered in some of the Macaronesian islands, together with associated vegetation, including trees.
The Euphorbia species tabaiba
and Euphorbia cactus are marker species defining the concept of the Macaronesian ecotype..
Most of the mammalian species in the laurisilva are bats, but two species of giant rats existed on the islands of Tenerife
and Gran Canaria
; they survived until shortly after human settlements were established on the islands. These giant rats of genus Canariomys
attained a weight of about 1 kg.
The kinglet
of Madeira is known as the Madeira firecrest, Regulus madeirensis Until recently, it was considered to be a subspecies, R. i. madeirensis, of the Common Firecrest R. ignicapillus. However, phylogenetic
analysis based on the cytochrome b
gene
showed that the Madeiran form is a distinct species.
The Azores Bullfinch
Is threatened and if it is to recover, the ecology of the northern archipelago of Macaronesia must be effectively restored. Projects attempting to re-establish the original laurel forest
habitat in the eastern monteverde of São Miguel are under way.
Some species of pigeons are endemic to Macaronesia
; Bolle's Pigeon
, the Laurel Pigeon
and Trocaz Pigeon
, are thought to be derived from island populations of the Columba palumbus. Other non-endemic species such as the Afep Pigeon
also occur on the island.
The Atlantic archipelagos of the Canaries, Azores
, and Madeira have a volcanic origin and they have never been part of a continent. The formation of Madeira started in the Miocene
and the island was substantially complete by 700,000 years ago. At various times in the past, the major islands of these archipelagos were all colonised by ancestral wood pigeons, which evolved on their respective islands in isolation from the mainland populations. In Azores
Islands, of extinct species laurel forest
mountain pigeon or Azores black pigeon . Mitochondrial
and nuclear
DNA
sequences suggest that the ancestor of Bolle's Pigeon
may have arrived in the Canaries about 5 mya, but an older lineage that gave rise to another Canarian endemic, the Laurel Pigeon
, C. junoniae, may date from 20 mya. The most recent wood pigeon arrival on Madeira was that which gave rise to the subspecies C. palumbus maderensis and Azores Wood Pigeon
C. palumbus azorensis.
The Trocaz Pigeon was formally described in 1829 by Karl Heineken
, a German medical doctor and ornithologist who was living on Madeira at the time. He recognised it as different from the now-extinct local form of the Common Wood Pigeon, which he called the "Palumbus", and noted that the two pigeons never interbred or habitually associated together. He suggested designating the new species by its local name, "trocaz". Trocaz is a variant of Portuguese torcaz, the Common Wood Pigeon; both words are ultimately derived from the Latin torquis, a collar, and refer to the bird's coloured neck patches. This is a monotypic species, although in the past Bolle's Pigeon was sometimes regarded as a subspecies
of the Trocaz Pigeon.
s of a vegetation
type which originally covered much of the Mediterranean Basin
when the climate
of the region was more humid
. With the drying of the Mediterranean Basin
during the Pliocene
, the laurel forests gradually retreated, replaced by more drought
-tolerant sclerophyll
plant communities. Most of the last remaining laurisilva forests around the Mediterranean are believed to have disappeared approximately 10,000 years ago at the end of the Pleistocene
, when the Mediterranean basin became drier and with a harsher climate, although some remnants of the laurel forest flora still persist in the mountains of southern Spain
, north-center of Portugal
and northern Morocco
, and two constituent species (Laurus nobilis
and Ilex aquifolium
) remain widespread. The location of the Macaronesian Islands in the North Atlantic Ocean moderated these climatic fluctuations, and maintained the relatively humid and mild climate which has allowed these forests to persist to the present day.
Over millions of years, these vegetation covered much of the tropic
s of Earth
. From a biogeographic
point of view, the tropics may extend beyond parallels of Cancer and Capricorn; e.g. the peninsula of Florida
in the United States
lies in the subtropics (latitude greater than 23° 26' N), but hosts many species characteristic of the New World tropics
.
One example is the translation of the Tertiary Atlantic laurisilva to its current location.
Many plants of the Macaronesian laurisilva have their closest relatives in geographically remote places like South Africa or South America, the genera Persea
, Ocotea
, and Maytenus
, for example, also appear in South American temperate evergreen, which testifies the ancient origin of these flora. Another interesting finding is the presence in various areas of the Mediterranean and the Caucasus
up to the Himalayas
of plant fossils around 20 million years old, from the Tertiary, very similar or identical to those currently living in Macaronesia.
This type of forest extended during the Cenozoic or Tertiary Era, more than 20 million years, over a wide area of the basin of the Mediterranean, Eurasia and north-west Africa where the climate the region were wetter. At that time there was a Tethys Sea that separated the ancient continents of Laurasia
and Gondwana
; this sea was much more open than the Mediterranean and ocean currents flowed in a different way, bringing tempering moisture and clima, in areas that currently do not have any influence. Subsequently, the Ice Age
which took place at the end of that period and for much of the Quaternary
forced the laurel forest
s to move to warmer southern regions, where conditions were more conducive to their survival, settling in this way on the northwest coast of Africa
and in the Macaronesian archipelagos.
During the Quaternary
glaciations and expansion of the polar ice caps, resulting in widespread cooling of the climate, the flora of central and southern Europe retreated to more southerly latitudes in search of milder conditions. Also the sea level was lower, with lands today submerged forming land bridges.
The end of glaciations coincided with the spread of deserts in North Africa, notably the Sahara, so this type of forest was reduced to those areas, which act as boundaries between temperate and tropical. At that time, the climate of southern Europe was warmer and wetter than today, and the vegetation that surrounded the ancient shores of the Mediterranean Sea was likely similar to that of the current Macaronesian laurisilva.
The laurel forests of Macaronesia are relics of the vegetation that originally covered the land from the Atlantic to the Caspian Sea before the Ice Age
. With the largest periodic drought in the Mediterranean climate due to climatic changes due to changes in ocean currents and continental drift during the Pliocene
, laurel forests gradually disappeared, replaced by plant communities of more drought tolerant sclerophyllous flora. Most of the last remaining temperate evergreen forests around the Mediterranean are believed to have disappeared about 10,000 years ago at the end of the Pleistocene
, when the Mediterranean basin became warmer and drier, although some remnants of the laurel forest flora still persist in the southern mountains in Spain, north-central Portugal and northern Morocco, and three constituent species, Laurus nobilis, Ilex aquifolium, and Hedera helix
, are still widespread. A remarkable adaptation is the asparagus
, which in the Canary Islands is preserved in the original form, a leafy vine, while in the rest of the Mediterranean has evolved into a thorny species. The location of the Macaronesian Islands in the North Atlantic Ocean moderated these climatic fluctuations, and maintained the relatively humid and mild climate that has allowed these cloud forest
s to persist until today.
Many of the then existing species became extinct because they could not cross the barriers posed by the Alpine Mountains and the Mediterranean, but others found refuge as a species relic
t in coastal enclaves and in the Macaronesian archipelagos, sufficiently far from the ice while protected by the oceanic influence of drying that caused the Sahara. In other parts of the world, including China, Africa or South America, the arrangement of ridges and mountain ranges extending in the direction from north to south, rather than serve as a barrier, permitted the plants' migration to more suitable areas, where they are survive to this day.
With the general warming of the atmosphere and the consequent withdrawal of the ice, flora tertiary survivors could not regain their range in southern Europe, as the new post-glacial climate was drier than that of the Tertiary, and to these new environmental requirements, the primitive tropical European flora evolved and gave rise to the present flora of the Mediterranean sclerophyll. Thus, the Mediterranean flora and fauna have a common origin.
At the same time, isolated from the mainland, the tertiary Macaronesian flora evolved independently, which has led to numerous endemic species. In fact, it should be noted that 50-55% of vascular plant species present in the Canary Islands are unique, and this proportion increases in more distant islands like Cape Verde, Azores and Madeira. Macaronesian laurel forest consists of about 25 tree species, 35 if the species that survive in nearby areas of Eurasia are added, while in the "laurisilva misionera" there are in total over 100 tree species; it is likely that the Atlantic laurel rainforest from the Tertiary had roughly this same number of species of "laurisilva misionera".
Laurel forest
Laurel forest is a subtropical or mild temperate forest, found in areas with high humidity and relatively stable and mild temperatures. They are characterized by tree species with evergreen, glossy, enlongated leaves, known as laurophyll or lauroide...
") is a subtropical forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
, found in areas with high humidity and relatively stable and mild temperatures. They are characterised by evergreen, glossy-leaved tree species that look alike with leaves of lauroide type. The members of the Laurel family (Lauraceae
Lauraceae
The Lauraceae or Laurel family comprises a group of flowering plants included in the order Laurales. The family contains about 55 genera and over 3500, perhaps as many as 4000, species world-wide, mostly from warm or tropical regions, especially Southeast Asia and South America...
) could be prominent, or in association.
Of particular note is the endemic
Endemic (ecology)
Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...
type of humid subtropical laurel forest
Laurel forest
Laurel forest is a subtropical or mild temperate forest, found in areas with high humidity and relatively stable and mild temperatures. They are characterized by tree species with evergreen, glossy, enlongated leaves, known as laurophyll or lauroide...
, macaronesian laurisilva, found on several of the Macaronesia
Macaronesia
Macaronesia is a modern collective name for several groups of islands in the North Atlantic Ocean near Europe and North Africa belonging to three countries: Portugal, Spain, and Cape Verde...
n islands of the North Atlantic and Macaronesian African mainland enclaves, namely Madeira Islands, the Azores
Azores
The Archipelago of the Azores is composed of nine volcanic islands situated in the middle of the North Atlantic Ocean, and is located about west from Lisbon and about east from the east coast of North America. The islands, and their economic exclusion zone, form the Autonomous Region of the...
, Cape Verde
Cape Verde
The Republic of Cape Verde is an island country, spanning an archipelago of 10 islands located in the central Atlantic Ocean, 570 kilometres off the coast of Western Africa...
Islands and the Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...
, a relict
Relict
A relict is a surviving remnant of a natural phenomenon.* In biology a relict is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas....
of the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
subtropical forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s, supporting numerous endemic species.
In Spanish
Spanish language
Spanish , also known as Castilian , is a Romance language in the Ibero-Romance group that evolved from several languages and dialects in central-northern Iberia around the 9th century and gradually spread with the expansion of the Kingdom of Castile into central and southern Iberia during the...
, the word "laurisilva" is used for every laurel forest: Laurisilva misionera, laurisilva valdiviana, etc.
Macaronesian Laurisilva Region
The laurisilva forests are found in the islands of MacaronesiaMacaronesia
Macaronesia is a modern collective name for several groups of islands in the North Atlantic Ocean near Europe and North Africa belonging to three countries: Portugal, Spain, and Cape Verde...
in the eastern Atlantic, in particular the Azores
Azores
The Archipelago of the Azores is composed of nine volcanic islands situated in the middle of the North Atlantic Ocean, and is located about west from Lisbon and about east from the east coast of North America. The islands, and their economic exclusion zone, form the Autonomous Region of the...
, Madeira Islands, and western Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...
, from 400 m to 1200 m elevation. Trees of the genera Apollonias
Apollonias
Apollonias is a genus of flowering plants belonging to the laurel family, Lauraceae. The genus includes from one to ten species of evergreen trees and shrubs from laurel forest habitat mainly in Macaronesian islands.-Description:...
(Lauraceae
Lauraceae
The Lauraceae or Laurel family comprises a group of flowering plants included in the order Laurales. The family contains about 55 genera and over 3500, perhaps as many as 4000, species world-wide, mostly from warm or tropical regions, especially Southeast Asia and South America...
), Ocotea
Ocotea
Ocotea is a genus of flowering plants belonging to the family Lauraceae. The genus includes over 200 species of evergreen trees and shrubs, distributed mostly in tropical and subtropical regions of Central and South America, the West Indies, also with a few species in Africa and Madagascar, and...
(Lauraceae), Persea
Persea
Persea is a genus of about 150 species of evergreen trees belonging to the laurel family, Lauraceae. The best-known member of the genus is the avocado, P. americana, widely cultivated in subtropical regions for its large, edible fruit.-Overview:...
(Lauraceae), Clethra
Clethra
Clethra is a genus of between 30-70 species of flowering shrubs or small trees. It is one of two genera in the family Clethraceae...
(Clethraceae), Dracaena
Dracaena (plant)
Dracaena is a genus of about 40 species of trees and succulent shrubs. In the APG III classification system, it is placed in the family Asparagaceae, subfamily Nolinoideae . It has also formerly been separated into the family Dracaenaceae or placed in the Agavaceae...
(Ruscaceae
Ruscaceae
Nolinoideae is a monocot subfamily of the family Asparagaceae in the APG III system of 2009. It was previously treated as a separate family, Ruscaceae s.l...
), and Picconia
Picconia
Picconia is a genus of flowering plants in the family Oleaceae.-Species:*Picconia azorica - endemic to the archipelago of the Azores*Picconia excelsa - tree up to 15m; Madeira, Canaries...
(Oleaceae
Oleaceae
Oleaceae are a family containing 24 extant genera and around 600 species of mesophytic shrubs, trees and occasionally vines. As shrubs, members of this family may be twine climbers, or scramblers.-Leaves:...
) are characteristic. The Madeira Islands laurel forest was designated a World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...
by UNESCO
UNESCO
The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations...
in 1999.
The forests are made up of laurel-leaved evergreen
Evergreen
In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...
hardwood
Hardwood
Hardwood is wood from angiosperm trees . It may also be used for those trees themselves: these are usually broad-leaved; in temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen.Hardwood contrasts with softwood...
tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
s, reaching up to 40 m in height. Many of the species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
are endemic
Endemic (ecology)
Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...
to the islands, and harbour a rich biota
Biota (ecology)
Biota are the total collection of organisms of a geographic region or a time period, from local geographic scales and instantaneous temporal scales all the way up to whole-planet and whole-timescale spatiotemporal scales. The biota of the Earth lives in the biosphere.-See...
of understorey plants, invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s, and bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s and bat
Bat
Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...
s.
Laurisilva formerly covered much of the mountain areas of Annobon
Annobón
Annobón may refer to:* Annobón Province* Annobonese language* Annobon people...
, Azores, Bioko
Bioko
Bioko is an island 32 km off the west coast of Africa, specifically Cameroon, in the Gulf of Guinea. It is the northernmost part of Equatorial Guinea with a population of 124,000 and an area of . It is volcanic with its highest peak the Pico Basile at .-Geography:Bioko has a total area of...
, Cape Verde
Cape Verde
The Republic of Cape Verde is an island country, spanning an archipelago of 10 islands located in the central Atlantic Ocean, 570 kilometres off the coast of Western Africa...
, Canary Islands, Madeira, São Tomé
São Tomé
-Transport:São Tomé is served by São Tomé International Airport with regular flights to Europe and other African Countries.-Climate:São Tomé features a tropical wet and dry climate with a relatively lengthy wet season and a short dry season. The wet season runs from October through May while the...
, Príncipe
Príncipe
Príncipe is the northern and smaller of the two major islands of the country of São Tomé and Príncipe lying off the west coast of Africa. It has an area of 136 km² and a population of approximately 5,000. The island is a heavily eroded volcano over three million years old, surrounded by other...
, other Atlantic islands, and locally on favourable wet climate microenvironments of the coast and coastal mountains of the north-west African mainland, but the forests have been much reduced in extent by logging
Logging
Logging is the cutting, skidding, on-site processing, and loading of trees or logs onto trucks.In forestry, the term logging is sometimes used in a narrow sense concerning the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard...
, clearance for agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
and grazing
Grazing
Grazing generally describes a type of feeding, in which a herbivore feeds on plants , and also on other multicellular autotrophs...
, and the invasion of exotic species. The most extensive laurisilva forests remain on Madeira, where they are found between 300 m and 1400 m altitude on the northern slope, and 700 m to 1600 m on the southern slope, and cover 149,5 km². In the Canary Islands, roughly 60 km² of laurisilva remain on Tenerife
Tenerife
Tenerife is the largest and most populous island of the seven Canary Islands, it is also the most populated island of Spain, with a land area of 2,034.38 km² and 906,854 inhabitants, 43% of the total population of the Canary Islands. About five million tourists visit Tenerife each year, the...
, smaller areas on La Palma
La Palma
La Palma is the most north-westerly of the Canary Islands. La Palma has an area of 706 km2 making it the fifth largest of the seven main Canary Islands...
, over 20 km² in Garajonay National Park
Garajonay National Park
Garajonay National Park is located in the center and north of the island of La Gomera, one of the Canary Islands . It was declared a national park in 1981 and a World Heritage Site by UNESCO in 1986...
on La Gomera
La Gomera
La Gomera is one of Spain's Canary Islands, located in the Atlantic Ocean off the coast of Africa. In area, it is the second-smallest of the seven main islands of this group.- Political organization :...
, and relict areas in Gran Canaria
Gran Canaria
Gran Canaria is the second most populous island of the Canary Islands, with a population of 838,397 which constitutes approximately 40% of the population of the archipelago...
. In the Azores, small patches of laurisilva forest remain on the islands of Pico
Pico Island
Pico Island , is an island in the Central Group of the Portuguese Azores noted for its eponymous volcano, Ponta do Pico, which is the highest mountain in Portugal, the Azores, and the highest elevation of the Mid-Atlantic Ridge...
, Terceira
Terceira Island
Referred to as the “Ilha Lilás” , Terceira is an island in the Azores archipelago, in the middle of the North Atlantic Ocean. It is one of the larger islands of the archipelago, with a population of 56,000 inhabitants in an area of approximately 396.75 km²...
, and São Miguel
São Miguel Island
São Miguel Island , nicknamed "The Green Island", is the largest and most populous island in the Portuguese Azores archipelago. The island covers and has around 140,000 inhabitants, 45,000 of these people located in the largest city in the archipelago: Ponta Delgada.-History:In 1427, São Miguel...
.
The Madeira laurisilva forests, the largest remaining stands, were declared a UNESCO
UNESCO
The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations...
World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...
in 1999. Predominant lauraceous
Lauraceae
The Lauraceae or Laurel family comprises a group of flowering plants included in the order Laurales. The family contains about 55 genera and over 3500, perhaps as many as 4000, species world-wide, mostly from warm or tropical regions, especially Southeast Asia and South America...
trees include Til (Ocotea foetens
Ocotea foetens
Ocotea foetens is a species of tree up to 40 m tall in the Lauraceae family. It is a common constituent in the laurisilva forests of the archipelagoes of Macaronesia: Madeira and Azores , and Canaries . It is commonly called "Til", "Tilo", "Stinkwood", Garoé, Oreodaphne foetens or Rain tree of...
), Loureiro (Laurus novocanariensis
Laurus novocanariensis
Laurus novocanariensis is a evergreen large shrub or tree with aromatic, shiny dark-green foliage. belonging to Laurus genus of evergreen trees belonging to the Laurel family, Lauraceae. The genus includes three species, whose diagnostic key characters often overlap . Under favorable conditions it...
), Vinhático (Persea indica
Persea indica
Persea indica is a species of plant in the Lauraceae family.It is found in the Azores, Madeira, and Canary Islands in Macaronesia. It is threatened by habitat loss.-Overview:...
), a valuable hardwood, and Barbosano (Apollonias barbujana); other important trees include Aderno (Heberdenia excelsa
Heberdenia excelsa
Heberdenia excelsa is a species of plant in the Myrsinaceae family.It is found in the Macaronesian archipelagoes, the Canary Islands , Azores, and Madeira, governed by Portugal and Spain. It is threatened by habitat loss.-Source:...
), Pau Branco (Picconia excelsa
Picconia excelsa
Picconia excelsa is a species of Picconia, endemic to Macaronesia, occurring on the Canary Islands and Madeira .-Description:...
), the Mocanos (Visnea mocanera
Visnea mocanera
Visnea mocanera is a species of plant in the Theaceae family.It is found in Madeira and Canary Islands in Macaronesia. It is threatened by habitat loss.-Source:* Bañares, A. et al. 1998. . Downloaded on 24 August 2007....
and Pittosporum coriaceum
Pittosporum coriaceum
Pittosporum coriaceum is a species of plant in the Pittosporaceae family. It is endemic to Macaronesia, and due to extinction in the Canary islands, it is now restricted to the Portuguese Madeira Islands....
), and Sanguinho (Rhamnus glandulosa
Rhamnus glandulosa
Rhamnus glandulosa Sanguinho in portuguese, is a species of plant in the Rhamnaceae family. It is found in Portugal and Spain. It is threatened by habitat loss...
), and the small trees or large shrubs Folhado (Clethra arborea
Clethra arborea
Clethra arborea, commonly known as the Lily of the Valley Tree, is a flowering plant in the genus Clethra. It is found in Macaronesia where it is native to Madeira, extinct in the Canary Islands, and considered an introduced species in the Azores...
) and Perado (Ilex perado). The forests support a diverse understorey of fern
Fern
A fern is any one of a group of about 12,000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem . They have stems, leaves, and roots like other vascular plants...
s and bryophyte
Bryophyte
Bryophyte is a traditional name used to refer to all embryophytes that do not have true vascular tissue and are therefore called 'non-vascular plants'. Some bryophytes do have specialized tissues for the transport of water; however since these do not contain lignin, they are not considered to be...
s, which both require moisture for reproduction, evergreen
Evergreen
In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...
climbing plants like Canarina canariensis, asparagus species
Asparagus (genus)
Asparagus is a genus in the plant family Asparagaceae, subfamily Asparagoideae. It comprises up to 300 species. Most are evergreen long-lived perennial plants growing from the understory as lianas, bushes or climbing plants. The best-known species is the edible Asparagus officinalis, commonly...
and Araliaceae
Araliaceae
Araliaceae is a family of flowering plants, also known as the Aralia family or Ivy family. The family includes 254 species of trees, shrubs, lianas and perennial herbaceous plants into 2 subfamilies...
s (Hedera helix
Hedera helix
Hedera helix is a species of ivy native to most of Europe and western Asia. It is labeled as an invasive species in a number of areas where it has been introduced.-Description:...
, Hedera canariensis
Hedera canariensis
Hedera canariensis is a species of Ivy which is native to the Atlantic coast in Canary islands and northern Africa. Its common name is the Canarian Ivy.-Description:...
) and of herbaceous plants
Herb
Except in botanical usage, an herb is "any plant with leaves, seeds, or flowers used for flavoring, food, medicine, or perfume" or "a part of such a plant as used in cooking"...
, including the Leitugas (Sonchus
Sonchus
Sonchus is a genus of flowering plants in the daisy family Asteraceae. Most of the species are annual herbs, a few are perennial, and some are even woody...
spp.), geraniums (Geranium maderense, G. palmatum and G. rubescens), the Estreleiras (Argyranthemum
Argyranthemum
Argyranthemum is a genus of flowering plants belonging to the family Asteraceae. Members of this genus are sometimes also placed in the genus Chrysanthemum....
spp.) and the endemic orchid Goodyera macrophylla.
Lanzarote and Fuerteventura are very close to the African mainland (96 km), and were even closer during the Ice Age
Ice age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
of the Quaternary
Quaternary
The Quaternary Period is the most recent of the three periods of the Cenozoic Era in the geologic time scale of the ICS. It follows the Neogene Period, spanning 2.588 ± 0.005 million years ago to the present...
(18,000 years ago, roughly 60 km). The vegetation is very similar to the basement floor of the eastern Canary Islands. A large number of plant species and some animals are common, mainly arthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s, but the most unusual given that many of these taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
are endemic to both regions, the insular and continental. Often displayed species vicarious
Vicarious
Vicarious may refer to:* Vicarious arousal, when someone witnessing a strong display of emotion begins to feel a similar emotion themselves.* Vicarious abuse , abuse committed on behalf of somebody else...
within a gender which, in turn, is endemic in both regions: Lotus marocanus / Lotus glaucus; Bubonium intrincatum / Bubonium sericeum; Euphorbia echinus y Euphorbia beaumieriana / Euphorbia handiensis; Kleinia anteuphorbium / Kleinia neriifolia; Lavandula maroccana / Lavandula multifida
Lavandula multifida
Lavandula multifida is a small plant, sometimes a shrub, native to the southern regions of the Mediterranean, including Iberia, Sicily and the Canary Islands.The stems are grey and wooly. Leaves are double pinnate...
; Sonchus leptocephalus / Warionia saharae.
The phytosociology
Phytosociology
Phytosociology is the branch of science which deals with plant communities, their composition and development, and the relationships between the species within them. A phytosociological system is a system for classifying these communities...
of these configurations was described in a paper by Rivas Goday and Esteve Chueca.
A large relict population of the drago
Dracaena (plant)
Dracaena is a genus of about 40 species of trees and succulent shrubs. In the APG III classification system, it is placed in the family Asparagaceae, subfamily Nolinoideae . It has also formerly been separated into the family Dracaenaceae or placed in the Agavaceae...
plant (Dracaena
Dracaena (plant)
Dracaena is a genus of about 40 species of trees and succulent shrubs. In the APG III classification system, it is placed in the family Asparagaceae, subfamily Nolinoideae . It has also formerly been separated into the family Dracaenaceae or placed in the Agavaceae...
) was recently discovered in some of the Macaronesian islands, together with associated vegetation, including trees.
The Euphorbia species tabaiba
Euphorbia atropurpurea
Euphorbia atropurpurea, called tabaiba majorera or tabaiba roja in Spanish, is a shrub in the family Euphorbiaceae native to Tenerife in the Canary Islands. It can reach 2 metres in height, and grows in ravines, and on slopes and terraces....
and Euphorbia cactus are marker species defining the concept of the Macaronesian ecotype..
Fauna
The decline of much of the endemic laurisilva fauna and flora is largely due to deforestation to accommodate agricultural expansion. This is accompanied by displacement of native flora by invasive alien weeds and crop plants.Most of the mammalian species in the laurisilva are bats, but two species of giant rats existed on the islands of Tenerife
Tenerife
Tenerife is the largest and most populous island of the seven Canary Islands, it is also the most populated island of Spain, with a land area of 2,034.38 km² and 906,854 inhabitants, 43% of the total population of the Canary Islands. About five million tourists visit Tenerife each year, the...
and Gran Canaria
Gran Canaria
Gran Canaria is the second most populous island of the Canary Islands, with a population of 838,397 which constitutes approximately 40% of the population of the archipelago...
; they survived until shortly after human settlements were established on the islands. These giant rats of genus Canariomys
Canariomys
Canariomys is an extinct genus of rodents that once existed on the islands of Tenerife and Gran Canaria, part of the Canary Islands, Spain...
attained a weight of about 1 kg.
The kinglet
Kinglet
The kinglets or crests are a small group of birds sometimes included in the Old World warblers, but are frequently given family status because they also resemble the titmice. The scientific name Regulidae is derived from the Latin word regulus for "petty king" or prince, and comes from the...
of Madeira is known as the Madeira firecrest, Regulus madeirensis Until recently, it was considered to be a subspecies, R. i. madeirensis, of the Common Firecrest R. ignicapillus. However, phylogenetic
Phylogenetics
In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...
analysis based on the cytochrome b
Cytochrome b
Cytochrome b/b6 is the main subunit of transmembrane cytochrome bc1 and b6f complexes. In addition, it commonly refers to a region of mtDNA used for population genetics and phylogenetics.- Function :...
gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
showed that the Madeiran form is a distinct species.
The Azores Bullfinch
Azores Bullfinch
The Azores Bullfinch , also known as the São Miguel Bullfinch, or locally in Portuguese as the Priolo, is an endangered passerine bird in the true finch family...
Is threatened and if it is to recover, the ecology of the northern archipelago of Macaronesia must be effectively restored. Projects attempting to re-establish the original laurel forest
Laurel forest
Laurel forest is a subtropical or mild temperate forest, found in areas with high humidity and relatively stable and mild temperatures. They are characterized by tree species with evergreen, glossy, enlongated leaves, known as laurophyll or lauroide...
habitat in the eastern monteverde of São Miguel are under way.
Some species of pigeons are endemic to Macaronesia
Macaronesia
Macaronesia is a modern collective name for several groups of islands in the North Atlantic Ocean near Europe and North Africa belonging to three countries: Portugal, Spain, and Cape Verde...
; Bolle's Pigeon
Bolle's Pigeon
The Bolle's Pigeon is a species of Columba genus of the family Columbidae, of doves and pigeons, which is endemic to the Canary Islands, Spain. This bird is named after the German naturalist Carl Bolle, who was the first to distinguish it from the Laurel Pigeon...
, the Laurel Pigeon
Laurel Pigeon
The Laurel Pigeon, White-tailed Laurel Pigeon, Paloma rabiche, is a species of bird in the Columba genus in the Columbidae family. It is a member of the family Columbidae of doves and pigeons, which is endemic to the Canary Islands, Spain...
and Trocaz Pigeon
Trocaz Pigeon
The Trocaz Pigeon, Madeira Laurel Pigeon or Long-toed Pigeon is a pigeon which is endemic to the island of Madeira. It is a mainly grey bird with a pinkish breast; its silvery neck patch and lack of white wing markings distinguish it from its close relative and probable ancestor, the Common Wood...
, are thought to be derived from island populations of the Columba palumbus. Other non-endemic species such as the Afep Pigeon
Afep Pigeon
The Afep Pigeon also known as the African Wood-Pigeon, or Gray Wood-Pigeon is a member of the Columbidae family which lives in Africa.Like many other pigeons, it mainly feeds on grain and seeds....
also occur on the island.
The Atlantic archipelagos of the Canaries, Azores
Azores
The Archipelago of the Azores is composed of nine volcanic islands situated in the middle of the North Atlantic Ocean, and is located about west from Lisbon and about east from the east coast of North America. The islands, and their economic exclusion zone, form the Autonomous Region of the...
, and Madeira have a volcanic origin and they have never been part of a continent. The formation of Madeira started in the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
and the island was substantially complete by 700,000 years ago. At various times in the past, the major islands of these archipelagos were all colonised by ancestral wood pigeons, which evolved on their respective islands in isolation from the mainland populations. In Azores
Azores
The Archipelago of the Azores is composed of nine volcanic islands situated in the middle of the North Atlantic Ocean, and is located about west from Lisbon and about east from the east coast of North America. The islands, and their economic exclusion zone, form the Autonomous Region of the...
Islands, of extinct species laurel forest
Laurel forest
Laurel forest is a subtropical or mild temperate forest, found in areas with high humidity and relatively stable and mild temperatures. They are characterized by tree species with evergreen, glossy, enlongated leaves, known as laurophyll or lauroide...
mountain pigeon or Azores black pigeon . Mitochondrial
Mitochondrion
In cell biology, a mitochondrion is a membrane-enclosed organelle found in most eukaryotic cells. These organelles range from 0.5 to 1.0 micrometers in diameter...
and nuclear
Cell nucleus
In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...
DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
sequences suggest that the ancestor of Bolle's Pigeon
Bolle's Pigeon
The Bolle's Pigeon is a species of Columba genus of the family Columbidae, of doves and pigeons, which is endemic to the Canary Islands, Spain. This bird is named after the German naturalist Carl Bolle, who was the first to distinguish it from the Laurel Pigeon...
may have arrived in the Canaries about 5 mya, but an older lineage that gave rise to another Canarian endemic, the Laurel Pigeon
Laurel Pigeon
The Laurel Pigeon, White-tailed Laurel Pigeon, Paloma rabiche, is a species of bird in the Columba genus in the Columbidae family. It is a member of the family Columbidae of doves and pigeons, which is endemic to the Canary Islands, Spain...
, C. junoniae, may date from 20 mya. The most recent wood pigeon arrival on Madeira was that which gave rise to the subspecies C. palumbus maderensis and Azores Wood Pigeon
Azores Wood Pigeon
The Azores Wood Pigeon, Columba palumbus azorica is an endemic subspecies of the Common Wood Pigeon in the Atlantic Azores islands of...
C. palumbus azorensis.
The Trocaz Pigeon was formally described in 1829 by Karl Heineken
Karl Heineken
Karl Heineken , also known as Carlos Heineken, was a German medical doctor and ornithologist. He lived on Madeira, a Portuguese island in Macaronesia, from 1826 until his death. He described the Trocaz Pigeon, a Madeiran endemic bird species...
, a German medical doctor and ornithologist who was living on Madeira at the time. He recognised it as different from the now-extinct local form of the Common Wood Pigeon, which he called the "Palumbus", and noted that the two pigeons never interbred or habitually associated together. He suggested designating the new species by its local name, "trocaz". Trocaz is a variant of Portuguese torcaz, the Common Wood Pigeon; both words are ultimately derived from the Latin torquis, a collar, and refer to the bird's coloured neck patches. This is a monotypic species, although in the past Bolle's Pigeon was sometimes regarded as a subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of the Trocaz Pigeon.
Origin
The laurisilva forests of Macaronesia are relictRelict
A relict is a surviving remnant of a natural phenomenon.* In biology a relict is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas....
s of a vegetation
Vegetation
Vegetation is a general term for the plant life of a region; it refers to the ground cover provided by plants. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader...
type which originally covered much of the Mediterranean Basin
Mediterranean Basin
In biogeography, the Mediterranean Basin refers to the lands around the Mediterranean Sea that have a Mediterranean climate, with mild, rainy winters and hot, dry summers, which supports characteristic Mediterranean forests, woodlands, and scrub vegetation...
when the climate
Climate
Climate encompasses the statistics of temperature, humidity, atmospheric pressure, wind, rainfall, atmospheric particle count and other meteorological elemental measurements in a given region over long periods...
of the region was more humid
Humidity
Humidity is a term for the amount of water vapor in the air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of water vapor and other constituents of air, and humidity is defined in terms of the water content of this mixture,...
. With the drying of the Mediterranean Basin
Messinian salinity crisis
The Messinian Salinity Crisis, also referred to as the Messinian Event, and in its latest stage as the Lago Mare event, was a geological event during which the Mediterranean Sea went into a cycle of partly or nearly complete desiccation throughout the latter part of the Messinian age of the Miocene...
during the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
, the laurel forests gradually retreated, replaced by more drought
Drought
A drought is an extended period of months or years when a region notes a deficiency in its water supply. Generally, this occurs when a region receives consistently below average precipitation. It can have a substantial impact on the ecosystem and agriculture of the affected region...
-tolerant sclerophyll
Sclerophyll
Sclerophyll is the term for a type of vegetation that has hard leaves and short internodes . The word comes from the Greek sclero and phyllon ....
plant communities. Most of the last remaining laurisilva forests around the Mediterranean are believed to have disappeared approximately 10,000 years ago at the end of the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
, when the Mediterranean basin became drier and with a harsher climate, although some remnants of the laurel forest flora still persist in the mountains of southern Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
, north-center of Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...
and northern Morocco
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...
, and two constituent species (Laurus nobilis
Bay Laurel
The bay laurel , also known as sweet bay, bay tree, true laurel, Grecian laurel, laurel tree, or simply laurel, is an aromatic evergreen tree or large shrub with green, glossy leaves, native to the Mediterranean region. It is the source of the bay leaf used in cooking...
and Ilex aquifolium
European Holly
Ilex aquifolium, holly, or european holly, is a species of holly native to western and southern Europe, northwest Africa and southwest Asia.- Overview :...
) remain widespread. The location of the Macaronesian Islands in the North Atlantic Ocean moderated these climatic fluctuations, and maintained the relatively humid and mild climate which has allowed these forests to persist to the present day.
Over millions of years, these vegetation covered much of the tropic
Tropic
A tropic can refer to:In geography, either of two circles of latitude:*Tropic of Cancer, at 23° 26' 16" N*Tropic of Capricorn, at 23° 26' 16" S...
s of Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
. From a biogeographic
Biogeography
Biogeography is the study of the distribution of species , organisms, and ecosystems in space and through geological time. Organisms and biological communities vary in a highly regular fashion along geographic gradients of latitude, elevation, isolation and habitat area...
point of view, the tropics may extend beyond parallels of Cancer and Capricorn; e.g. the peninsula of Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
lies in the subtropics (latitude greater than 23° 26' N), but hosts many species characteristic of the New World tropics
Neotropic
In biogeography, the Neotropic or Neotropical zone is one of the eight terrestrial ecozones. This ecozone includes South and Central America, the Mexican lowlands, the Caribbean islands, and southern Florida, because these regions share a large number of plant and animal groups.It is sometimes used...
.
One example is the translation of the Tertiary Atlantic laurisilva to its current location.
Many plants of the Macaronesian laurisilva have their closest relatives in geographically remote places like South Africa or South America, the genera Persea
Persea
Persea is a genus of about 150 species of evergreen trees belonging to the laurel family, Lauraceae. The best-known member of the genus is the avocado, P. americana, widely cultivated in subtropical regions for its large, edible fruit.-Overview:...
, Ocotea
Ocotea
Ocotea is a genus of flowering plants belonging to the family Lauraceae. The genus includes over 200 species of evergreen trees and shrubs, distributed mostly in tropical and subtropical regions of Central and South America, the West Indies, also with a few species in Africa and Madagascar, and...
, and Maytenus
Maytenus
Maytenus is a genus of flowering plants in the staff vine family, Celastraceae. Members of the genus are distributed throughout Central and South America, Southeast Asia, Micronesia and Australasia, the Indian Ocean and Africa...
, for example, also appear in South American temperate evergreen, which testifies the ancient origin of these flora. Another interesting finding is the presence in various areas of the Mediterranean and the Caucasus
Caucasus
The Caucasus, also Caucas or Caucasia , is a geopolitical region at the border of Europe and Asia, and situated between the Black and the Caspian sea...
up to the Himalayas
Himalayas
The Himalaya Range or Himalaya Mountains Sanskrit: Devanagari: हिमालय, literally "abode of snow"), usually called the Himalayas or Himalaya for short, is a mountain range in Asia, separating the Indian subcontinent from the Tibetan Plateau...
of plant fossils around 20 million years old, from the Tertiary, very similar or identical to those currently living in Macaronesia.
This type of forest extended during the Cenozoic or Tertiary Era, more than 20 million years, over a wide area of the basin of the Mediterranean, Eurasia and north-west Africa where the climate the region were wetter. At that time there was a Tethys Sea that separated the ancient continents of Laurasia
Laurasia
In paleogeography, Laurasia was the northernmost of two supercontinents that formed part of the Pangaea supercontinent from approximately...
and Gondwana
Gondwana
In paleogeography, Gondwana , originally Gondwanaland, was the southernmost of two supercontinents that later became parts of the Pangaea supercontinent. It existed from approximately 510 to 180 million years ago . Gondwana is believed to have sutured between ca. 570 and 510 Mya,...
; this sea was much more open than the Mediterranean and ocean currents flowed in a different way, bringing tempering moisture and clima, in areas that currently do not have any influence. Subsequently, the Ice Age
Ice age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
which took place at the end of that period and for much of the Quaternary
Quaternary
The Quaternary Period is the most recent of the three periods of the Cenozoic Era in the geologic time scale of the ICS. It follows the Neogene Period, spanning 2.588 ± 0.005 million years ago to the present...
forced the laurel forest
Laurel forest
Laurel forest is a subtropical or mild temperate forest, found in areas with high humidity and relatively stable and mild temperatures. They are characterized by tree species with evergreen, glossy, enlongated leaves, known as laurophyll or lauroide...
s to move to warmer southern regions, where conditions were more conducive to their survival, settling in this way on the northwest coast of Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
and in the Macaronesian archipelagos.
During the Quaternary
Quaternary
The Quaternary Period is the most recent of the three periods of the Cenozoic Era in the geologic time scale of the ICS. It follows the Neogene Period, spanning 2.588 ± 0.005 million years ago to the present...
glaciations and expansion of the polar ice caps, resulting in widespread cooling of the climate, the flora of central and southern Europe retreated to more southerly latitudes in search of milder conditions. Also the sea level was lower, with lands today submerged forming land bridges.
The end of glaciations coincided with the spread of deserts in North Africa, notably the Sahara, so this type of forest was reduced to those areas, which act as boundaries between temperate and tropical. At that time, the climate of southern Europe was warmer and wetter than today, and the vegetation that surrounded the ancient shores of the Mediterranean Sea was likely similar to that of the current Macaronesian laurisilva.
The laurel forests of Macaronesia are relics of the vegetation that originally covered the land from the Atlantic to the Caspian Sea before the Ice Age
Ice age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
. With the largest periodic drought in the Mediterranean climate due to climatic changes due to changes in ocean currents and continental drift during the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
, laurel forests gradually disappeared, replaced by plant communities of more drought tolerant sclerophyllous flora. Most of the last remaining temperate evergreen forests around the Mediterranean are believed to have disappeared about 10,000 years ago at the end of the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
, when the Mediterranean basin became warmer and drier, although some remnants of the laurel forest flora still persist in the southern mountains in Spain, north-central Portugal and northern Morocco, and three constituent species, Laurus nobilis, Ilex aquifolium, and Hedera helix
Hedera helix
Hedera helix is a species of ivy native to most of Europe and western Asia. It is labeled as an invasive species in a number of areas where it has been introduced.-Description:...
, are still widespread. A remarkable adaptation is the asparagus
Asparagus
Asparagus officinalis is a spring vegetable, a flowering perennialplant species in the genus Asparagus. It was once classified in the lily family, like its Allium cousins, onions and garlic, but the Liliaceae have been split and the onion-like plants are now in the family Amaryllidaceae and...
, which in the Canary Islands is preserved in the original form, a leafy vine, while in the rest of the Mediterranean has evolved into a thorny species. The location of the Macaronesian Islands in the North Atlantic Ocean moderated these climatic fluctuations, and maintained the relatively humid and mild climate that has allowed these cloud forest
Cloud forest
A cloud forest, also called a fog forest, is a generally tropical or subtropical evergreen montane moist forest characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level. Cloud forests often exhibit an abundance of mosses covering the ground and...
s to persist until today.
Many of the then existing species became extinct because they could not cross the barriers posed by the Alpine Mountains and the Mediterranean, but others found refuge as a species relic
Relic
In religion, a relic is a part of the body of a saint or a venerated person, or else another type of ancient religious object, carefully preserved for purposes of veneration or as a tangible memorial...
t in coastal enclaves and in the Macaronesian archipelagos, sufficiently far from the ice while protected by the oceanic influence of drying that caused the Sahara. In other parts of the world, including China, Africa or South America, the arrangement of ridges and mountain ranges extending in the direction from north to south, rather than serve as a barrier, permitted the plants' migration to more suitable areas, where they are survive to this day.
With the general warming of the atmosphere and the consequent withdrawal of the ice, flora tertiary survivors could not regain their range in southern Europe, as the new post-glacial climate was drier than that of the Tertiary, and to these new environmental requirements, the primitive tropical European flora evolved and gave rise to the present flora of the Mediterranean sclerophyll. Thus, the Mediterranean flora and fauna have a common origin.
At the same time, isolated from the mainland, the tertiary Macaronesian flora evolved independently, which has led to numerous endemic species. In fact, it should be noted that 50-55% of vascular plant species present in the Canary Islands are unique, and this proportion increases in more distant islands like Cape Verde, Azores and Madeira. Macaronesian laurel forest consists of about 25 tree species, 35 if the species that survive in nearby areas of Eurasia are added, while in the "laurisilva misionera" there are in total over 100 tree species; it is likely that the Atlantic laurel rainforest from the Tertiary had roughly this same number of species of "laurisilva misionera".
See also
- Laurel forestLaurel forestLaurel forest is a subtropical or mild temperate forest, found in areas with high humidity and relatively stable and mild temperatures. They are characterized by tree species with evergreen, glossy, enlongated leaves, known as laurophyll or lauroide...
- Cloud forestCloud forestA cloud forest, also called a fog forest, is a generally tropical or subtropical evergreen montane moist forest characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level. Cloud forests often exhibit an abundance of mosses covering the ground and...
- Mediterranean forests, woodlands, and scrubMediterranean forests, woodlands, and scrubMediterranean forests, woodlands, and scrub biome, defined by the World Wildlife Fund, characterized by dry summers and rainy winters. Summers are typically hot in low-lying inland locations but can be cool near some seas, as near San Francisco, which have a sea of cool waters...
- SatoyamaSatoyamais a Japanese term applied to the border zone or area between mountain foothills and arable flat land. Literally, sato means arable and livable land or home land, and yama means mountain...