2015年11月17日星期二

Two evolutions of disruptive camouflage found in horned praying mantises

A research about horned praying mantises was published by scientists from The Cleveland Museum of Natural History on Nov. 16, 2015 online in the journal Systematic Entomology. This research was led by Dr. Gavin Svenson and assisted by his colleagues. It revised the horned praying mantis group and traced the evolution of its distinctive camouflage features. The researchers identified a new genus and new tribe of praying mantis and found that disruptive camouflage evolved twice within the group. More recently, they discovered the re-evolution of a special leg lobe that disguises the body profile to help the insect hide from predators. The research team studied the origins of sixteen features that provide disruptive crypsis for the Central and South American horned praying mantises of the subfamily Vatinae, all of which contribute to their camouflage strategy. A head process or horn and leafy looking lobes on the legs were found in the features. The study covered 33 species and nearly 400 specimens from Museum collections in the United States, South America, Europe and insects Svenson recently sampled from South America. We all know that praying mantises depend on camouflage to protect themselves from predators, but scientists still know little about how their body structures benefit to crypsis evolvement. Now they have known that two mantis lineages evolved structural camouflage millions of years apart in very similar ways. It shows that re-evolution occurred, and also proves that the developmental mechanisms controlling cryptic features may be more ancient than the camouflaged mantises themselves. The scientists got the idea that leafy lobes on the middle and hind legs evolved during the first origin of the horned mantises. Then, one lineage focused on a camouflage strategy and started to accumulate other leg lobes, an extend head process or horn, even lobes on the abdomen, while others lost the early evolved leg lobes and relied only on coloration to mix with vegetation. But there is another tendency that the smaller lineage of mantises within this color camouflaged group began to gain disruptive cryptic features about twenty million years later after the re-evolution of those same early originating leg lobes. The second condition was turned to a strategy of disruptive camouflage appears to have followed a remarkably similar path as the first through the accumulation of leg lobes in the same positions, and a similar extended head process or horn. The scientists thought that the latter one was likely to be controlled by genetic and developmental mechanisms present now. In fact, the ability of evolving camouflage was already in the genetic toolkit of the lineage and the features emerged again when it was good for survival. Svenson even considered the mantis groups have disruptive camouflage, and the praying mantises had evolved the ability very early, and they can control it freely in many kinds of ways. Read more as you like:http://www.cusabio.com/Polyclonal-Antibody/TSPAN31-Antibody-FITC-conjugated--11098198.html

没有评论:

发表评论