Camponotus saundersi
Encyclopedia
Camponotus saundersi is a species
of ant
found in Malaysia and Brunei
, belonging to the genus
of Carpenter ant
s. Workers can explode suicidally as an ultimate act of defense, an ability it has in common with several other species in this genus and a few other insects. The ant has an enormously enlarged mandibular
(abdomen) gland, many times the size of a normal ant, which produces defense adhesive secretions.
, a term coined by Maschwitz and Maschwitz (1974) . Two oversized, poison-filled mandibular glands run the entire length of the ant's body. When combat takes a turn for the worse, the worker ant violently contracts its abdominal muscles to rupture its gaster
at the intersegmental fold, which also bursts the mandibular glands, thereby spraying a sticky secretion in all directions from the anterior region of its head. The glue, which also has corrosive properties and functions as a chemical irritant, entangles and immobilizes all nearby victims.
Direct observation by Jones (2004) found that C. saundersi adhesive secretions range from bright white at the end of the wet season to cream or pale yellow in the dry season and start of the wet season. These variations in coloration represent a shift in internal pH
, likely due to seasonal changes in diet.
in C. saundersi is common during territorial battles with other ant species or groups. Territorial weaver ants (Oecophylla smaragdina) are known to stalk and attack C. saundersi for territory as well as for predation. Self-sacrifice of C. saundersi workers is likely to help the colony as a whole by ensuring that the colony retains its foraging territory. Therefore, such behavior would continue within a population given that the behavior was already genetically present within the majority of workers.
in C. saundersi is used as defense against predation by other arboreal arthropods (weaver ants, spiders), which are believed to be the main predatory threat to C. saundersi for two reasons:
Jones, et al (2004) identified the following chemicals within the secretion:
Phenols
Aliphatics
Terpenoids
Both 2,4-Dihydroxyacetophenone and 2-Methyl-5,7-dihydroxychromone are phenolic ketones which cause the pH-dependent color changes of the secretion.
(6R)-(E)-2,6-Dimethyl-2-octen-1,8-dionic acid is an acylic monoterpene previously undocumented in insects. However, the chemical is well known to be a urinary metabolite
in mammals, with overproduction resulting in toxic acidosis
in various 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...
of ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
found in Malaysia and Brunei
Brunei
Brunei , officially the State of Brunei Darussalam or the Nation of Brunei, the Abode of Peace , is a sovereign state located on the north coast of the island of Borneo, in Southeast Asia...
, belonging to the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of Carpenter ant
Carpenter ant
Carpenter ants are large ants indigenous to many parts of the world. They prefer dead, damp wood in which to build nests. They do not eat it, however, unlike termites. Sometimes carpenter ants will hollow out sections of trees. The most likely species to be infesting a house in the United States...
s. Workers can explode suicidally as an ultimate act of defense, an ability it has in common with several other species in this genus and a few other insects. The ant has an enormously enlarged mandibular
Submandibular gland
The paired submandibular glands are salivary glands located beneath the floor of the mouth. In humans, they account for 70% of the salivary volume and weigh about 15 grams. Unstimulated in humans, the percentage contribution to whole saliva; ~25% Parotid, Submandibular and Sublingual ~ 67% and...
(abdomen) gland, many times the size of a normal ant, which produces defense adhesive secretions.
Defenses
Its defensive behaviours include self-destruction by autothysisAutothysis
Autothysis is the process where an animal destroys itself via an internal rupturing or explosion of an organ which ruptures the skin. The term was proposed by Maschwitz and Maschwitz in 1974 to describe the defensive mechanism of the carpenter ant . It is caused by a contraction of muscles around a...
, a term coined by Maschwitz and Maschwitz (1974) . Two oversized, poison-filled mandibular glands run the entire length of the ant's body. When combat takes a turn for the worse, the worker ant violently contracts its abdominal muscles to rupture its gaster
Gaster
The gaster is the bulbous posterior portion of the metasoma found in Apocrita Hymenoptera . This begins with abdominal segment III on most ants, but some make a postpetiole out of segment III, in which case the gaster begins with abdominal segment IV....
at the intersegmental fold, which also bursts the mandibular glands, thereby spraying a sticky secretion in all directions from the anterior region of its head. The glue, which also has corrosive properties and functions as a chemical irritant, entangles and immobilizes all nearby victims.
Direct observation by Jones (2004) found that C. saundersi adhesive secretions range from bright white at the end of the wet season to cream or pale yellow in the dry season and start of the wet season. These variations in coloration represent a shift in internal pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
, likely due to seasonal changes in diet.
Territorial defense
AutothysisAutothysis
Autothysis is the process where an animal destroys itself via an internal rupturing or explosion of an organ which ruptures the skin. The term was proposed by Maschwitz and Maschwitz in 1974 to describe the defensive mechanism of the carpenter ant . It is caused by a contraction of muscles around a...
in C. saundersi is common during territorial battles with other ant species or groups. Territorial weaver ants (Oecophylla smaragdina) are known to stalk and attack C. saundersi for territory as well as for predation. Self-sacrifice of C. saundersi workers is likely to help the colony as a whole by ensuring that the colony retains its foraging territory. Therefore, such behavior would continue within a population given that the behavior was already genetically present within the majority of workers.
Defense against predation
AutothysisAutothysis
Autothysis is the process where an animal destroys itself via an internal rupturing or explosion of an organ which ruptures the skin. The term was proposed by Maschwitz and Maschwitz in 1974 to describe the defensive mechanism of the carpenter ant . It is caused by a contraction of muscles around a...
in C. saundersi is used as defense against predation by other arboreal arthropods (weaver ants, spiders), which are believed to be the main predatory threat to C. saundersi for two reasons:
- 1. Jones (2004) noted through direct observation that C. saundersi is “remarkably sensitive” to even slight leaf vibration.
- 2. The inherent adhesive qualities of C. saundersi’s secretion are more effective in immobilizing the appendages of arthropods as opposed to those of vertebrates.
Chemicals
The "toxic glue" of C. saundersi is predominately composed of polyacetates, aliphatic hydrocarbons, and alcohols. Branched-skeleton lactones and methylated isocoumarins produced in the hindgut function as trail pheromones, while straight-chain hydrocarbons and esters produced in the Dufour‘s glands act as alarm pheromones in C. saundersi and related species.Jones, et al (2004) identified the following chemicals within the secretion:
Phenols
Phenols
In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of a hydroxyl group bonded directly to an aromatic hydrocarbon group...
- m-cresolM-Cresolm-Cresol, also 3-methylphenol, is a phenol, with formula C6H4.Amongst its uses it can be used as a solvent for dissolving polymers, most notably the conducting polymer polyaniline...
(traces found), a corrosive compound - 2,4-Dihydroxyacetophenone
- 2-Methyl-5,7-dihydroxychromone
- OrcinolOrcinolOrcinol is a natural phenolic organic compound that occurs in many species of lichens including Rocella tinctoria and Lecanora. It can be formed by fusing extract of aloes with potash....
(traces found)
Aliphatics
Aliphatic compound
In organic chemistry, aliphatic compounds are acyclic or cyclic, non-aromatic carbon compounds.Thus, aliphatic compounds are opposite to aromatic compounds.- Structure :...
- UndecaneUndecaneUndecane is a liquid alkane hydrocarbon with the chemical formula CH39CH3. It is used as a mild sex attractant for various types of moths and cockroaches, and an alert signal for a variety of ants. It has 159 isomers....
- 2-Heptanone2-Heptanone2-Heptanone, or methyl n-amyl ketone, is a ketone with the molecular formula C7H14O. It is a colorless, water-white liquid with a banana-like, fruity odor....
(traces found)
Terpenoids
Terpenoid
The terpenoids , sometimes called isoprenoids, are a large and diverse class of naturally occurring organic chemicals similar to terpenes, derived from five-carbon isoprene units assembled and modified in thousands of ways. Most are multicyclic structures that differ from one another not only in...
- CitronellalCitronellalCitronellal or rhodinal or 3,7-dimethyloct-6-en-1-al is a monoterpenoid, the main component in the mixture of terpenoid chemical compounds that give citronella oil its distinctive lemon scent....
- CitronellolCitronellolCitronellol, or dihydrogeraniol, is a natural acyclic monoterpenoid. Both enantiomers occur in nature. -Citronellol, which is found in citronella oils, including Cymbopogon nardus , is the more common isomer. -Citronellol is found in the oils of rose and Pelargonium geraniums.Citronellol is...
- Citronellic acid
- Isopulegol-(E)-2,6-Dimethyl-2-octen-1,8-dionic acid
Both 2,4-Dihydroxyacetophenone and 2-Methyl-5,7-dihydroxychromone are phenolic ketones which cause the pH-dependent color changes of the secretion.
(6R)-(E)-2,6-Dimethyl-2-octen-1,8-dionic acid is an acylic monoterpene previously undocumented in insects. However, the chemical is well known to be a urinary metabolite
Metabolite
Metabolites are the intermediates and products of metabolism. The term metabolite is usually restricted to small molecules. A primary metabolite is directly involved in normal growth, development, and reproduction. Alcohol is an example of a primary metabolite produced in large-scale by industrial...
in mammals, with overproduction resulting in toxic acidosis
Acidosis
Acidosis is an increased acidity in the blood and other body tissue . If not further qualified, it usually refers to acidity of the blood plasma....
in various species.