{"id":3245,"date":"2021-11-18T10:00:00","date_gmt":"2021-11-18T10:00:00","guid":{"rendered":"https:\/\/modernsciences.org\/staging\/4414\/?p=3245"},"modified":"2021-11-04T07:43:01","modified_gmt":"2021-11-04T07:43:01","slug":"100-million-year-old-lacewing-larvae-trapped-in-myanmar-amber-reveal-their-intriguing-features","status":"publish","type":"post","link":"https:\/\/modernsciences.org\/staging\/4414\/100-million-year-old-lacewing-larvae-trapped-in-myanmar-amber-reveal-their-intriguing-features\/","title":{"rendered":"100-Million-Year-Old Lacewing Larvae Trapped in Myanmar Amber Reveal Their Intriguing Features"},"content":{"rendered":"\n

For decades now, scientists have been on a constant search for finding clues about our planet\u2019s vast, ancient past. While creatures of old like dinosaurs and mammoths have long played poster child to public awareness about these majestic animals and plants, there are countless other ancient animals out there that carry with them as much interest as their more-famous contemporaries.<\/p>\n\n\n\n

Of particular interest for a certain study published in the journal Scientific Reports<\/em> are insects that fall under the insect order Neuroptera<\/em>. The order\u2019s name is roughly Greek for \u201csinew wings,\u201d given by the fact that their wings showcase extensive branching; these insects are also known as the net-winged insects<\/em>.<\/p>\n\n\n\n

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Members of the insect order Neuroptera<\/em> include the brown lacewings; the species represented in the image above is Micromus posticus<\/em>. (Lucier\/Wikimedia Commons, 2011)\u00a0 <\/figcaption><\/figure><\/div>\n\n\n\n

These insects have been around for quite some time now, having first appeared in the fossil record in rocks dated to the end of the Permian Period some 250 million years ago. These insects have since evolved to scatter across the world, and are composed of several well-known members, including antlions, lacewings, and snakeflies.<\/p>\n\n\n\n

The insects in this study, however, are so old that they\u2019ve been identified from individuals trapped in 100-million-year-old amber, or fossilized tree resin. This particular study, which explored the odd features displayed by larvae trapped in amber and frozen in time, was spearheaded by Joachim Haug, zoologist from the Ludwig-Maximilians-Universit\u00e4t in Munich.<\/p>\n\n\n\n

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These particular lacewing larvae specimens were trapped in amber dated to the Cretaceous Period, sitting at around 100 million years old. These larvae seem peculiar at first glance because lacewings undergo complete metamorphosis once they reach a certain age\u2014meaning all these \u201cextra\u201d features on the larvae don\u2019t even stick around on the insects\u2019 bodies for long. (Haug et al, 2021) <\/figcaption><\/figure><\/div>\n\n\n\n

Of course, amber wouldn\u2019t be the only place you\u2019d look into when searching for fossilized insects; insects locked in time inside usual fossil rock are out there, much like the 49-million-year-old beetle fossil called \u201cAttenborough\u2019s Beauty.<\/a>\u201d This particular study, however, was rooted in findings from amber obtained in Myanmar\u2019s Hukawng Valley.<\/p>\n\n\n\n

What\u2019s odd about these ancient larvae, however, is the fact that they seem so ornate. Features like giant mandibles, long antennae, limbs, and necks are all visible on these insects locked in time. The features seem reminiscent of predatory insects, but as they\u2019ve been locked inside amber and are fossilized, scientists don\u2019t know for certain what these features are really for.

“As in the case of all modern species of lacewings, these larvae were probably predators, but we know nothing about their prey,\u201d said Haug in a statement.<\/p>\n\n\n\n

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The larval stage of green lacewings (Chrysoperla rufilabris<\/em>) appear quite different from their adult forms, but they nevertheless lack much standout features in this part of their lives; this appears to stand in contrast to the outlandish features present in Neuroptera<\/em> larvae from the study by Haug and team, which are stuck fossilized in 100 million-year-old Myanmar amber. (Schulz\/Wikimedia Commons, 2016) <\/figcaption><\/figure><\/div>\n\n\n\n

They do know, however, that these features come as a stark contrast to what has been previously understood about these insects, wherein they undergo holometabolism<\/em> once they reach a certain age in life\u2014a process otherwise known as complete metamorphosis<\/em>. The same phenomenon occurs in butterflies as they emerge from cocoons created by their previous caterpillar selves.<\/p>\n\n\n\n

It has thus been assumed by some experts that these insect larvae don\u2019t necessarily need standout features like giant jaws and long antennae while in their larval stage; after all, they\u2019ll quite literally grow out of it in the end. To the scientists, larvae don\u2019t really need these features until they reach adulthood, where they get a second chance through complete metamorphosis. And true enough, living Neuropterans like lacewings retain relatively \u201cbasic\u201d larval forms, and only grow their standout features once they metamorphose into their adult forms.<\/p>\n\n\n\n

Haug and team write in their paper: “The enormous evolutionary and ecological success of Holometabola <\/em>has been attributed to the niche differentiation between the adult and the often highly aberrant-appearing larva. […] All these notions indirectly imply that holometabolan larvae are to a certain degree constrained in their possibilities to evolve morphologically diverse forms.”<\/p>\n\n\n\n

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More fossilized insect larvae trapped in amber from Myanmar\u2019s Hukawng Valley are shown above, with their peculiar outstanding features on full display. Haug and team believe their surprise with the difference in larval features between extant and extinct Neuroptera<\/em> larvae show the scientific community\u2019s \u201cignorance of larval forms.\u201d (Haug et al, 2021) <\/figcaption><\/figure><\/div>\n\n\n\n

To Haug and team, this feeling of surprise with their results really shows more of the scientific community\u2019s \u201c\u2018ignorance of larval forms\u2019, and of how complex they can sometimes be,\u201d writes news source ScienceAlert.<\/p>\n\n\n\n

The eventual loss of these larval features in modern-day Neuropterans may play a role in why we understand so little about these larval forms, but the authors believe that \u201cthere is no principal constraint that hinders holometabolan larvae to develop such structures,\u201d as they wrote on their paper.<\/p>\n\n\n\n

Finally, the authors continued: “[These results] demonstrate, again, that considering only modern-day fauna will lead to the impression that certain morphological or developmental constraints exist, but which are in fact only artifacts due to ‘filtering history’.\u201d<\/p>\n\n\n\n

(For more insect finds, check out the potential ocean-spanning migrations taken by globe skimmer dragonflies<\/a>.)<\/p>\n\n\n\n

References<\/h2>\n\n\n\n