Researchers Find Early Evidence of Mimicry Among Insects

Monday, August 30, 2010

Fossil

Fossil lacewings

A research team including Biodiversity Institute Entomology Curator Michael S. Engel has concluded that well-preserved lacewing fossils from northeastern China represent the earliest evidence of leaf mimicry among insects.

Many extant insects, including some mantises, treehoppers and butterflies mimic the leaves of flowering plants to hide from predators. The historical origin of this adaptive mimicry has remained unclear because of a dearth of fossil finds. The researchers found the remains of two lacewings whose features are strikingly similar to the leaves of certain Mesozoic gymnosperms thought to predate the evolution of flowering plants. These characteristics include elongated forewings that bear undulating margins, coloration resembling leaflets, complex venation and branches resembling leaf shafts.

In a paper published today in the Proceedings of the National Academy of Sciences, the researchers suggest that the lacewings likely rested and fed on the feather-like leaves, remaining still or swaying in the breeze to fool predators such as insectivorous dinosaurs, primitive birds, and mammals. When these gymnosperms gave way to flowering plants, the lacewings likely became prone to predation, suggesting that leaf mimicry evolved before the rise of flowering plants, according to the researchers.

Authors of the paper, “Ancient pinnate leaf mimesis among lacewings,” were Engel, who is professor of Ecology and Evolutionary Biology at KU, and Professor Dong Ren, Post-doc Yongjie Wang, Visiting Professor Chungkun Shih, and Associate Professor Yunyun Zhao, all of the Capital Normal University;  Professor Zhiqi Liu of the China Agricultural University; and Dr. Xin Wang of the Nanjing Institute of Geology and Palaeontology.

News Type: 
Research News