Butterfly tongue existed before flowering plants, says new study

Newly-found fossils suggest moths and butterflies have been on Earth for at least 200 million years- at least 70 million years longer than previously thought. Shown here is primitive moth that has a proboscis that can suck up fluid. The scale bar is 1

According to oldest fossils studied to date, flowering plants appeared around 130 million years ago, 70 million years after the Triassic mass-extinction event or when these insects lived. "But that would be 50 million years later than what the wings were saying".

As Ben Guarino of the Washington Post reports, a new study has uncovered evidence suggesting that butterflies and moths had proboscises millions of years before flowers came into existence.

This is a living representative of a primitive Glossata, moths that have a proboscid that suck up fluids like nectar.

"What we've found is that these butterflies and moths with mouth parts were feeding on pollen droplets of gymnosperm seeds - from conifers related to pines, seed plants without fruits and flowers". The accepted theory up to now has been that the sucking proboscis only emerged at that point as a product of coevolution between flowers and the insects that pollinate them.

But even Charles Darwin called the mysterious evolution of flowering plants "an abominable mystery".

Butterflies are thought to exist alongside flowers, sucking nectar from them as part of a attractive rule of nature. "They were feeding off the cone-borne seeds - mainly as a source of water". "These insects later transferred their feeding preference onto angiosperms, and, as a result, ended up co-evolving with flowers where they function to transfer pollen as they feed on nectar".

"If you find the hollow scales", van Eldijk told Rebecca Hersher of NPR, "you know the innovation of the proboscis must have occurred before that". Some were solid and compact, which was not particularly unusual; previous research has shown that this structure was typical of early moths and butterflies, which used mandibles to chomp their food.

Researchers analysed and compared the fossilised wing scales to those of existing species. They found that the fossils were closely related to animals of the modern-day Glossata sub group which has a long proboscis

Given their complexity, and the time it would've taken to evolve to have such complex features, these fossils push the calculated age of glossatan moths back by about 70 million years to the Late Triassic "refuting ancestral association of the group with flowering plants", the researchers wrote in the study.

The mass extinction event 201 million years ago wiped out an estimated 35 percent of all species, which makes the survival and diversification of Lepidoptera all the more remarkable.

"By studying how insects and their evolution was affected by dramatic greenhouse warming at the start of the Jurassic, we hope to provide insight into how insects might respond to the human-induced climate change challenges we face today", van Eldijk said. "These are organic extractions after you've dissolved away the minerals in the samples and you're looking at anything that is organic". They generally treated these as a distraction from their real work, and focused instead on pollen and spores as a continuous record for understanding past ecosystems. There are other things.

Researchers studying deep-drilling cores have long noticed odd flecks of material in their samples, possibly from insects. Ninety-nine percent is plant debris.

We'll never look at pond scum the same way again.

The project required linking a range of evidence, akin to a scientific detective story, said Strother.



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