photo by: Digital Atlas of Ancient Life project

Anadara aequalitas from the Middle Pleistocene Bermont Formation of Palm Beach County, Fla. (Creative Commons BY-NC-SA 4.0)

No need to worry if you are raising a sluggish child, especially if your child is a mollusk.

A recent University of Kansas study has been gaining international attention with its suggestion that laziness might be a fruitful strategy for survival. But the lead author of the study, Luke Strotz, a postdoctoral researcher at KU’s Biodiversity Institute and Natural History Museum, says the study doesn’t necessarily apply to individual humans.

The research is based on mollusk fossils, “but I would like to think the results are a genuine phenomenon,” Strotz said. “I am talking about species concepts here and how any entire species responds in a sort of physiological sense.”

Mollusk are invertebrate animals, like snails, slugs, mussels and octopuses. They have a soft body — most have outer shells — and live in aquatic or damp environments.

The study, “Metabolic rates, climate and macroevolution: a case study using Neogene molluscs,” has been published in the Proceedings of the Royal Society B.

The question asked was could you look at the probability of extinction of a species based on energy intake of an organism?

It involved finding some sort of representative metabolism for that whole species and then looked at how much energy they intake and how much energy they use.

“The species who do more of that are taking more in, and are more likely to go extinct than those species who do less of that, and that essentially is the story,” Strotz said.

The research isn’t saying all extinctions are predicated on this.

“It’s not a be-all and end-all of extinction; that’s not the case,” Strotz said. “But what this study does for the first time is show that metabolism and physiology is a component of extinction and no one has done that before. No one has shown that previously.”

photo by: Kathy Hanks

Luke Strotz is a postdoctoral researcher at KU’s Biodiversity Institute and Natural History Museum. Strotz, photographed Thursday, Aug. 23, 2018, at KU, is receiving international attention for a recent study on mollusk fossils.

Strotz didn’t expect the results he found. He thought he would discover the opposite.

“Just because we see something at the lower level of the individual doesn’t mean it scales up to the level of the species,” Strotz said. “Biology is quite complex as we move up from individuals to populations, to species, to whole communities of species we do not expect phenomena that apply at lower levels to necessarily apply at higher levels.” But this did.

About a year ago, Strotz began thinking of the idea of looking at the probability of extinction of a species based on energy intake of an organism. He co-authored the work with KU’s Julien Kimmig, collection manager at the Biodiversity Institute; Bruce Lieberman, KU professor of ecology and evolutionary biology; and Erin Saupe, at Oxford University.

It took a solid year’s work of studying the fossils. He says the human angle got played up in the British media. It doesn’t bother him, because it draws people to the work.

“I think the most interesting side here is anything that potentially predicts the likelihood of extinction or adds to our understanding is important to us, why the species that exist today are here and why those organisms are here is because they survived extinction,” he said.

What Strotz hopes people realize is that although extinction is complex, researchers are discovering what causes and drives extinction over time.

“We are going through fundamental changes across the earth associated with climate change, and temperature is a driver of metabolism,” he said.

“Plus, how is that going to affect biodiversity on the planet? It’s a very complex story, but this is helping us build up that story,” Strotz said.