Study suggests venom helped form new fish, insect species

08 August 2021 18:43 STI

Swansea [UK], Aug 8 (ANI): The venom has contributed to the extraordinary diversity of insects and fish, the most species-rich groups of invertebrates and vertebrates in the animal kingdom, according to the findings of a recent study.
The research results were published in the journal BMC Ecology and Evolution.
Poisonous fish and insects diversify about twice as fast as their non-venomous counterparts, research has shown.
The venom provides an effective means of repelling predators or catching prey, which can allow species to exploit more opportunities in their environment, potentially leading to the formation of new species as they diversify into their ecology.
Over a million insect species have been identified to date, representing three-quarters of all invertebrate species on Earth. There are 31,269 species of fish, which make up almost half of all vertebrate species.
Today, about 10 percent of fish families and 16 percent of insect families contain poisonous species – from stingrays and catfish to wasps and mosquitoes. Research has shown that the venom has evolved independently at least 19-20 times in fish and at least 28 times in insects during their evolutionary history.
Although biologists have long examined the drivers of biodiversity, the role of venom in relation to the most diverse groups – insects and fish – had not been fully considered.

This is where the new research led by Swansea comes in. The team, led by Dr Kevin Arbuckle of the Department of Biosciences, carried out the first large-scale test to find out whether the venom contributes to the diversity of insect and fish species.
By showing that the venom evolved several times during the evolutionary history of insects and fish and that it was associated with faster rates of diversification, the researchers presented evidence that the venom contributed in ways significant to the diversity of species in these “super-radiations”.
“Our results prove that the venom played a role in creating the diversity of insects and fish, which respectively have the highest number of species among invertebrates and vertebrates,” said Dr Kevin Arbuckle of the University of Swansea, Principal Investigator.
“Venom is not the only factor behind the species richness of these animal groups, but we show that it played an important but hitherto unrecognized role in the generation of the astonishing diversity that we see today among insects and fish, ”added Dr Arbuckle.
“Although tentative, the pattern of timing in the origins of poisonous fish suggests tantalizing clues as to what drove the evolution of their venom. Unlike insects, where venom has evolved fairly evenly throughout their history, most of the origins of fish venom were concentrated in the Late Cretaceous and Eocene periods, ”continued Dr Arbuckle.
“Mosasaurs – the aquatic behemoths made famous in the Jurassic World series – were born and peaked in diversity during the late Cretaceous period, a time when other large groups of marine predators were in decline. Likewise, whales were born and peaked in diversity in the Eocene, when most other large marine predators became extinct at the end of the Cretaceous mass extinction, which killed the dinosaurs, ”the Dinosaur explained. Dr Arbuckle.
“It is believed that early whales and mosasaurs were active predators with similar movement styles. Accordingly, we cautiously assume that most of the origins of fish venom were related to similar predation pressures imposed by mosasaurs. at the end of the Cretaceous and at the beginning of whales in the Eocene ”, concluded Dr. Arbuckle. (ANI)