白亜紀の昆虫はすでに多様な防御戦略を持っていた(Insects already had a variety of defense strategies in the Cretaceous)

2023-12-21

2023-12-20 ミュンヘン大学(LMU)

◆LMUとGreifswald、Rostockの研究者は、ミャンマーのアンバーから得られた保存状態の良い昆虫の化石を調査しました。1億年前の白亜紀においても、昆虫の幼虫は捕食者から身を守るためのさまざまな進化した構造や戦略を持っていたことが明らかになりました。
◆例えば、蚊帳蛾の幼虫は様々な植物や動物の素材を背中に運び、これで偽装。最も古いサソリムシの幼虫は特殊な毛を持ち、これによって偽装材料をくっつけていました。これらの発見は、過去の多様な防御戦略が存在していたことを示し、現在の生物多様性の危機への理解に寄与しています。

<関連情報>

ミャンマーの琥珀の化石から、白亜紀のホロメタボラン昆虫の幼虫の対捕食戦略の多様性が証明される Fossils in Myanmar amber demonstrate the diversity of anti-predator strategies of Cretaceous holometabolan insect larvae

Carolin Haug, Joachim T. Haug, Gideon T. Haug, Patrick Müller, Ana Zippel, Christine Kiesmüller, Joshua Gauweiler, Marie K. Hörnig
iScience Published: December 3, 2023
DOI:https://doi.org/10.1016/j.isci.2023.108621

Highlights

•Review of different defensive strategies of holometabolan larvae in Kachin amber
•New cases including hymenopteran and hangingfly caterpillars were found
•Modern and now extinct strategies were present in Cretaceous in multiple lineages
•Strategies may have evolved convergently as result of similar selective pressures

Summary

Holometabolan larvae are a major part of the animal biomass and an important food source for many animals. Many larvae evolved anti-predator strategies and some of these can even be recognized in fossils. A Lagerstätte known for well-preserved holometabolan larvae is the approximately 100-million-year-old Kachin amber from Myanmar. Fossils can not only allow to identify structural defensive specializations, but also lifestyle and even behavioral aspects. We review here the different defensive strategies employed by various holometabolan larvae found in Kachin amber, also reporting new cases of a leaf-mining hymenopteran caterpillar and a hangingfly caterpillar with extensive spines. This overview demonstrates that already 100 million years ago many modern strategies had already evolved in multiple lineages, but also reveals some cases of now extinct strategies. The repetitive independent evolution of similar strategies in distantly related lineages indicates that several strategies evolved convergently as a result of similar selective pressures.