Rapid evolution fails to save butterflies from extinction in face of human-induced change

Date:  May 9, 2018

Source:  University of Plymouth

The evolution of wild species, adapting them to human management practices, can cause localised extinctions when those practices rapidly change. And in a new study published in Nature, Professors Michael C. Singer and Camille Parmesan have used more than 30 years of research to fully document an example of this process.

A large, isolated population of a North American butterfly evolved complete dependence on an introduced European weed to the point where the continued existence of the butterfly depended on the plant's availability. The insects then became locally extinct when humans effectively eliminated that availability, confirming a prediction made by the same authors in a 1993 Nature paper.

Thus the advent of cattle ranching more than 100 years ago set an eco-evolutionary trap that the insects obligingly fell into, and the trap was sprung when humans suddenly removed the cattle, withdrawing their 'gift', and driving the butterflies to extinction.

European conservation biologists have long believed this to be the process underlying many local extinctions across Europe, and this study provides the first hard evidence of the process in action in real time. It also foreshadows an increasing importance of maintaining historical land use practices, including cattle ranching, as conservation measures in North America.

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Strange sea-dwelling reptile fossil hints at rapid evolution after mass extinction

 Date: May 23, 2016

Source: Field Museum

For a long time, scientists believed that the early marine reptiles that came about after the great Permian-Triassic mass extinction evolved slowly, but the recent discovery of a strange new fossil brings that view into question. The newly described Sclerocormus parviceps is a marine reptile called an ichthyosauriform, and its strange features (short snout, long, whip-like tail) are really different from many of its relatives, revealing that marine reptiles evolved and diversified after the extinction more quickly than previously thought.

Two hundred and fifty million years ago, life on earth was in a tail-spin--climate change, volcanic eruptions, and rising sea levels contributed to a mass extinction that makes the death of the dinosaurs look like child's play. Marine life got hit hardest--96% of all marine species went extinct. For a long time, scientists believed that the early marine reptiles that came about after the mass extinction evolved slowly, but the recent discovery of a strange new fossil brings that view into question.

In a paper published in Scientific Reports, paleontologists describe a new marine reptile, Sclerocormus parviceps, an ichthyosauriform that's breaking all the rules about what ichthyosaurs are like.

Ichthyosaurs were a massive group of marine reptiles that lived around the time of the earliest dinosaurs. Most of them looked a little bit like today's dolphins--streamlined bodies, long beak-like snouts, and powerful tail fins. But the new species is something of a black sheep. It has a short snout (its species name even means "small skull"), and instead of a tail with triangular flukes (think of a fish's tail-fins), it had a long, whip-like tail without big fins at the end. And while many ichthyosaurs had conical teeth for catching prey, Sclerocormus was toothless and instead seems to have used its short snout to create pressure and suck up food like a syringe. In short, it's really different from most of its relatives, and that tells scientists something important about evolution.

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Honey bees rapidly evolve to overcome new disease

August 19, 2015 by Laura Petersen

An international research team has some good news for the struggling honeybee, and the millions of people who depend on them to pollinate crops and other plants.

These valuable pollinators have faced widespread colony losses over the past decade, largely due to the spread of a predatory mite called Varroa destructor. But the bees might not be in as dire a state as it seems, according to research recently published in Nature Communications.

Researchers found a population of wild bees from around Ithaca, New York, which is as strong today as ever, despite the mites invading the region in the mid-1990s.

"They took a hit, but they recovered," said Alexander Mikheyev, a professor at the Okinawa Institute of Science and Technology Graduate University (OIST) in Japan and lead paper author. "The population appears to have developed genetic resistance."

Mikheyev and his collaborators at OIST and Cornell University studied the population genetics of the wild colony by comparing the DNA of specimens collected in 1977 with bees collected from the same forest in 2010. To conduct the study, they developed a new DNA analysis tool that works especially well for degraded DNA stored in museum samples.

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Black widow spider venom unveiled: The fast evolution of a potent toxin

Date:

January 6, 2015

Source:

Society for Integrative and Comparative Biology (SICB)

Summary:

New research shows rapid evolution has helped to make the venom of black widow spiders so toxic.

Dr. Jessica Garb of the University of Massachusetts, Lowell, along with a team of collaborators in the US and the UK, has been attacking these questions by studying the spider's genetics, protein expression, and venom content, searching for clues about just how the widow spider's venom evolved to be so potent.

The most potent neurotoxins present in black widow venom are called latrotoxins, which takes its name from the group of widow spiders known as Latrodectus. The most toxic of these latrotoxins is alpha-latrotoxin, a devastatingly debilitating chemical that hijacks the body's own internal communications, the electrical and chemical signaling of the nervous system.

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Florida lizards evolve rapidly, within 15 years and 20 generations

Date:

October 23, 2014

Source:

University of Texas at Austin

Summary:

Scientists working on islands in Florida have documented the rapid evolution of a native lizard species -- in as little as 15 years -- as a result of pressure from an invading lizard species, introduced from Cuba.

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Environmental change 'triggers rapid evolution'

By Mark KinverEnvironment reporter, BBC News

Researchers were surprised how quickly the mites evolved as a result of environmental changes

Changes to their surroundings can trigger "rapid evolution" in species as they adopt traits to help them survive in the new conditions, a study shows.

Studying soil mites in a laboratory, researchers found that the invertebrates' age of maturity almost doubled in just 20-or-so generations.

It had been assumed that evolutionary change only occurred over a much longer timescale.

The findings have been published in the journal Ecology Letters.

"What this study shows for the first time is that evolution and ecology go hand-in-hand," explained co-author Tim Benton, professor of population ecology at the University of Leeds, UK.

"The implicit assumption has always been, from Darwin onwards, that evolution works on long timescale and ecology works on short timescales.

"The thinking was that if you squash a population or you change the environment then nothing will happen from an evolutionary point-of-view for generations and generations, for centuries."

Running wild

Prof Benton said that the soil mites experiment was set up to help shed light on whether the change in the size of harvested fish species, such as North Atlantic cod, was a result of an evolutionary change.

"The advantage of what we have done is that we have got free-running populations of organisms that do their own thing," he told BBC News.

The findings mean that managing populations will have to take into account evolutionary factors

"You cannot do those sort of experiment with large organisms that live in the wild."

Read on:  http://www.bbc.co.uk/news/science-environment-22039872