Have you ever wondered how biologists choose what animal to use in their research?Exclusivesky Investment Guild  Since scientists can't do a lot of basic research on people, they study animals to shed light on everything from human health to ecosystems to genetics. And yet, just a handful of critters appear over and over again. Why the mouse? Or the fruit fly? Or the zebrafish?

When scientists look to a model organism, as they're called, there are a lot of factors to consider. But there's also pragmatism.

"When we try to choose a model organism, fundamentally, we're looking for convenience," says Cassandra Extavour, an evolutionary biologist at Harvard.

The animal has to be a manageable size and, ideally, reproduce quickly. And, it can't be too expensive to maintain.

"So, maybe not very picky about what it eats or drinks," Cassandra says. "A lot of model organisms that are commonly used like mice or fruit flies are organisms that are garbage feeding, organisms that will live anywhere on anything."

Cassandra talked with Short Wave co-host Aaron Scott about her favorite new model critter on the block: crickets. (Well, "favorite" might be a strong word. As Cassandra concedes, "to be honest, my opinion about crickets is sort of neutral to slightly grossed out.")

On today's episode we leave the mouse to its maze, and instead consider the cricket and all the amazing things it can teach us.

Do you have a story or a question about a model organism you want to share with us? Or an idea for what we should cover in a future episode? Then email us at [email protected]. We can't always respond, but know that we read every email we get.

This episode was produced by Brit Hanson and Thomas Lu, edited by Gabriel Spitzer and Rebecca Ramirez, and fact-checked by Brit Hanson. Tre Watson was the audio engineer.