To avoid the hungry sass of predators , members of the animal kingdom have evolved some fascinating “ do n’t eat me ” signals ; some of which are truthful , droop to enemies that they are toxicant , whereas others are a clever ruse . Some cyanide - stuffed milliped , for example , pass off an eerie teal glow to admonish of their perniciousness . But interestingly , it turns out that , for at least one particular metal money , this bioluminescence did not in fact evolve as a defense mechanics , but rather tohelp them copewith the stresses of living in a red-hot , dry environment . This intriguing discovery has been published inProceedings of the National Academy of Sciences .
Found solely scuttling around three tidy sum ranges in California , Motyxia , or the Sierra luminous millipede , is a grouping of blind , cyanide - producing arthropods known for their ability to emit light . These bioluminescent microbe produce their distinctive glow by means of molecules calledphotoproteinswhich sire lighting upon combination with oxygen or otheroxidizing agents- things that contribute oxygen or steal electrons in chemic reaction .
Research has shown that not only does the luminescenceintensifywhen the animals are handled , but also that some glow brighter than others . By examining how much this brightness varies between species , National Geographicpoints out , then it might be possible to hunt the evolutionary origins of this trait . So , bugologist fromVirginia Techand the University of Arizona began collecting specimens from the wilderness , include non - glowing controls for comparison , for appraise their luminescence level .
One specie they canvass , Xystocheir bistipita , had not been seensince its uncovering back in 1967and was assumed to be non - luminescent . But to their surprise , the hemipteron start beam in their laboratory , stimulate suspicion that this millepede may really be a misbranded member of theMotyxiagroup . Later genetic analytic thinking by the team revealed that this was indeed the case , so the enigmatic species was renamedMotyxia bistipita .
paradigm credit : National Geographic Society Expeditions Council .
The investigator then began liken the genome of the members of theMotyxiagenus , include its newest member , in parliamentary procedure to examine inherited relationship . After constructing an evolutionary tree , the researcher quantify the brightness of their characteristic glowing photographically and then enquire their toxicity grade by take care how much nitril they possessed in their specialized glands .
Interestingly , theyfoundthat the milliped ’ bioluminescence uprise inMotyxia’scommon ancestor and then grew brighter over time . Furthermore , species living at lower elevations , such asM. bistipita , beam less than their relation at higher elevation . SinceM. bistipita’shabitat is much hotter and dry than hemipterous insect living further up the hatful , the research worker reasoned that their glow may not have in fact evolve as a warning signaling for predators , but or else to assist them deal with the stresses of such a climate .
At higher temperatures , animate being contend to control the spirit level of highly reactive , oxygen - contain speck holler reactive atomic number 8 metal money , such as peroxide , which can lead to cellular stress . However , photoproteins can really mop up these harmful corpuscle , reducing the scathe to the cell that would otherwise ensue whilst also produce light source .
But when the members of theMotyxiagroup began to migrate to higher ALT with a greater hazard of predation , the hemipterous insect repackaged this luminescence arrangement as a warning signal . This was endorse by the observance that species containing larger loudness of cyanide were bright than their slightly less toxic twin .
“ This find clarify the evolutionary origin of many complex trait , not just bioluminescence , ” lead author Paul Marek said in astatement .
