Gens (behaviour)
Encyclopedia
In animal behaviour
, a gens (pl. gentes) or host race is a host-specific lineage
of a brood parasite
species
. Brood parasites such as cuckoo
s, which use multiple host species to raise their chicks, evolve
different gentes, each one specific to its host species. This specialisation allows the parasites to lay eggs that mimic those of their hosts, which in turn reduces the chances of the eggs being rejected by the hosts.
The exact mechanisms of the evolution and maintenance of gens is still a matter of some research. However, it is believed that in Common Cuckoos
, gens-specific properties are sex-linked and lie on the W chromosome
of the female. Male cuckoos, which like all male birds have no W chromosome, are able to mate with females of any gens, and thereby maintain the cuckoo as one species.
Ethology
Ethology is the scientific study of animal behavior, and a sub-topic of zoology....
, a gens (pl. gentes) or host race is a host-specific lineage
Lineage (evolution)
An evolutionary lineage is a sequence of species, that form a line of descent, each new species the direct result of speciation from an immediate ancestral species. Lineages are subsets of the evolutionary tree of life. Lineages are often determined by the techniques of molecular systematics.-...
of a brood parasite
Brood parasite
Brood parasites are organisms that use the strategy of brood parasitism, a kind of kleptoparasitism found among birds, fish or insects, involving the manipulation and use of host individuals either of the same or different species to raise the young of the brood-parasite...
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...
. Brood parasites such as cuckoo
Cuckoo
The cuckoos are a family, Cuculidae, of near passerine birds. The order Cuculiformes, in addition to the cuckoos, also includes the turacos . Some zoologists and taxonomists have also included the unique Hoatzin in the Cuculiformes, but its taxonomy remains in dispute...
s, which use multiple host species to raise their chicks, evolve
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
different gentes, each one specific to its host species. This specialisation allows the parasites to lay eggs that mimic those of their hosts, which in turn reduces the chances of the eggs being rejected by the hosts.
The exact mechanisms of the evolution and maintenance of gens is still a matter of some research. However, it is believed that in Common Cuckoos
Common Cuckoo
The Common Cuckoo is a member of the cuckoo order of birds, Cuculiformes, which includes the roadrunners, the anis and the coucals....
, gens-specific properties are sex-linked and lie on the W chromosome
ZW sex-determination system
The ZW sex-determination system is a system that determines the sex of offspring in birds, some fish and crustaceans such as the giant river prawn, some insects , and some reptiles, including Komodo dragons...
of the female. Male cuckoos, which like all male birds have no W chromosome, are able to mate with females of any gens, and thereby maintain the cuckoo as one species.