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A University of Arizona biologist recently received a $1.3 million grant from NASA to conduct a four-year study of which properties of life are universal and, therefore, might exist extraterrestrially.

Richard Michod portrait

Photo: UA News

Richard Michod, head of the UA Department of Evolutionary Biology.

Richard Michod, head of UA Department of Evolutionary Biology, said NASA recognizes that as scientists start to spot water and evidence that points to simple life in places, such as the Martian polar caps, it wants to know if that can be connected to earthly evolution.

In other words, what did life on Earth go through, that life elsewhere would have also gone through? That’s where Michod and his research come in.

“What I pitched to NASA is, where hierarchical organization units form into groups and become new units should be occurring wherever life is found.”

His primary source of interest is a tiny alga known as volvocine algae. It existed in single-cell form and became multi-cellular later, Michod said. He wonders what led it to do that.

“Cells by themselves can be individuals, but when they’re in our body, they’re parts of our body,” he said.

It’s a part of the hierarchy of life. The main idea in the research is that living organisms tend to clump together when it benefits them: Elk move about in herds; ants form colonies; even humans at the top of the food chain come together into communities.

The reason for such clustering usually has something to do with food or safety, something that allows the organism to survive for longer and reproduce more. Michod said.

But, there’s a trade-off.

“When you have a lot of neighbors nearby, you’re being bathed in their waste products and they, of course, are competing with you for resources,” he said.

However, in spite of that disadvantage, living beings get more out of clumping together, bringing organisms to the ultimate step in clumping: when an organism sacrifices something to benefit the group.

What brings about that first act of altruism is what Michod said he wants to find.

“About a billion years ago there was this big transition to multi-cellularity,” and volvocine algae made an early, simple, altruistic act at the time, Michod said. Some cells gave up their ability to reproduce.

Somewhere, deep down in the genes of these algae, Michod said, he thinks he will find what caused them to start acting altruistically, to put the greater good ahead of individual success.

“There was a gene that when expressed in a cell, keeps the cell small,” he said. “The cell staying small means it can’t divide and it can’t reproduce.”

It saves energy that would be spent on reproduction to propel the community of algae into a better place, where other cells will reproduce.

He said that altruism is easily seen in the human world, with people clumping together first for safety, then for the common good by specializing, becoming farmers, hunters, artisans and warriors.

Then, people gained the ability to act with the good of the community higher than their own, a cycle that has continually replayed itself over the history of Earth.

If that is how life evolved to thrive on Earth, perhaps it went through the same or similar elsewhere, Michod said. Maybe, on the seas of Europa, or on Titan, or in some other solar system, life is going through the same process.