“Researchers examined Anadara aequalitas, a species of bivalve, as part of a study on the relationship between metabolism and individual, species, and community survival. They found that lower metabolism can enhance survival at all levels”

The Next Mass Extinction Might Be About Survival of the Laziest  /  December 17, 2018

n. A theory that species with lower metabolisms are less likely to go extinct.

“If you are a mollusk and you’re reading these words, chances are you’re prone to idleness and sloth. Good for you! In a new study of shellfish from the past 5 million years, scientists found that species with a greater chill factor are less likely to fizzle out—a phenomenon they dub survival of the laziest. It’s well known that high-strung, type A behavior is bad for your health. But the discovery that metabolic rate affects the longevity of not just organisms but also species is intriguing, and it raises the hopeful question: Could this work for humans too? If so, we just might have an edge in the next mass extinction. See, primates like us have a low resting metabolism: When we kick back, we burn half as many calories as other mammals. (So long, squirrels.) And we like to kick back. So is “survival of the ­fittest” passé? In the way it’s sometimes been twisted, to rationalize bullying and oppression, yes. By “fittest,” Darwin didn’t mean the most powerful; he meant those best suited to their environment. In truth, indolence can be a kind of fitness. Sedentary species use less energy, so in lean times they may outlast those with bigger appetites. But observe: It’s the frugal use of resources, not laziness per se, that is key. And let’s be honest fellow humans—sustainability isn’t exactly our forte. So, yeah, that New Year’s resolution about getting more exercise? Maybe you better stick with that.”

a river snail

‘Survival of The Laziest’ Is How Some Species Approach Evolution’
by Peter Dockrill  /  22 August 2018

“People will tell you laziness is bad. Get up and be active, they say. Move your body around, and it won’t just keep you fit, it could even keep you young. That’s good advice, but new research suggests being inherently lazy isn’t always as bad as is made out – and could actually be an evolutionary survival mechanism that defends slacker species from the oblivion of extinction. “We wondered, ‘Could you look at the probability of extinction of a species based on energy uptake by an organism?'” explains palaeontologist Luke Strotz from the University of Kansas. The answer, it turns out, is yes. At least for molluscs. Strotz and his team analysed almost 300 species of mollusc – including aquatic molluscs, but also snails and slugs – that have inhabited the Western Atlantic since the Pliocene epoch began some 5.33 million years ago. Not all of them lasted the distance. And that’s where things get interesting. “We found a difference for mollusc species that have gone extinct over the past 5 million years and ones that are still around today,” Strotz says. “Those that have gone extinct tend to have higher metabolic rates than those that are still living. Those that have lower energy maintenance requirements seem more likely to survive than those organisms with higher metabolic rates.”

Arcinella cornuta was included in a new large-data study of fossil and extant bivalves and gastropods in the Atlantic Ocean that suggests laziness might be a fruitful strategy for survival of individuals, species and even communities of species”

In a sense, of course, this isn’t altogether surprising. Energy keeps animals alive, and it stands to reason that animals that require more of it to function could be more vulnerable, especially over periods lasting millions of years. Up until now, though, this hypothesis was largely just assumed, but now it’s been observed. In the researchers’ mollusc microcosm, it was the ‘lazy’ snails, slugs, and scallops – or rather the species exhibiting a low basal metabolic rate (BMR) – that enjoyed better chances of pulling through.  “Maybe in the long term the best evolutionary strategy for animals is to be lassitudinous and sluggish – the lower the metabolic rate, the more likely the species you belong to will survive,” explains one of the team, evolutionary biologist Bruce Lieberman.

“Instead of ‘survival of the fittest,’ maybe a better metaphor for the history of life is ‘survival of the laziest’ or at least ‘survival of the sluggish.'” The researchers are eager to emphasise that their laziness proxy of BMR isn’t the only factor affecting mollusc survival, but it’s thought to be one of the integral mechanisms that help to drive extinction, particularly in species that aren’t spread over a diverse geographical area. “For instance, the difference we observe between BMR of extinct and extant species may reflect variation in a constellation of organismic traits such as developmental rate, time to maturity, lifespan and population size, with a primary causal factor driving these differences being variation in the rate of energy uptake,” the authors write in their paper.

“A study of over 300 species of molluscs that have lived and died in the Atlantic over the past five million years found that those with high metabolisms were the most likely to be extinct.”

Of course, what’s good for mollusc species is not necessarily good for me and you. So should we aspire to sluggishness? Should we be the slug? Unfortunately, the answer is no. Just because mollusc species with naturally low BMRs have enjoyed better survival prospects since basically forever ago doesn’t mean individual human beings can somehow ‘opt in’ to this metabolic magic. It doesn’t work that way. “You can’t just decide to be lazy as an individual and expect to live longer,” Strotz explained to Inverse. That said, the researchers think their finding may be generalisable to other marine creatures, and they say there’s a chance it could extend to other kinds of animals too, including vertebrates and critters who walk on land. At the human scale, of course – a world away from the non-concerns of slacker snails – we have bigger fish to fry. Laziness isn’t our saviour. In terms of survival, it’s the exact opposite. “Humanity’s laziness, when it comes to trying to arrest the changes to the planet we are causing, may be the biggest peril our own species faces,” Lieberman explained to The Guardian. “But in a nutshell our work indicates that being sluggish can make you more likely to survive. So, here’s to a nap, after we solve our planet’s environmental crisis.”

The findings are reported in Proceedings of the Royal Society B.


the RIGHT to be LAZY