Snails!

I know we are are focused on the behavior on Donald Trump and no one cares about any other issue. But here’s a post devoted to a life form slightly more evolved than the Republican candidate: snails. Unfortunately, a lot of snail species are going extinct.

Beyond that, there’s actually a lot that we can learn from snails. “From the most practical standpoint, snails have a few pretty interesting characteristics that tell us we should probably pay attention,” says snail researcher Rebecca Rundell, assistant professor at State University of New York. For one thing, their shells—which they carry with them their entire lives (because they’d die without them)—are made of calcium carbonate, which provides a record of their lives. Unlike plant husks or insect exoskeletons, these shells tend to persist after a snail has died, leaving behind a valuable tool for researchers. “We can look in marine sediment and pockets of soil for evidence of past ecological communities, and thus evidence for environmental change in a particular area,” she says.

Living snails can also serve as indicators when something is wrong with the environment, something we’re already seeing with ocean acidification. “If snails in the ocean that make their shells, their protection, exclusively from calcium carbonate are having trouble building them, then that means the ocean is in big trouble,” Rundell says.

They can provide similar clues on land, where land snails often have particularly narrow habitat requirements. “They need certain levels of moisture, shade, and decaying matter,” Rundell says. “When they don’t have this, they start dying off.” That’s just the start: if tiny land snails start to disappear, it’s important to ask what might happen next. “It might give you a chance to change course,” she says, “to detect subtle changes that humans might not otherwise be able to see until it is too late.”

Snails also help us to answer bigger questions. “The fact that many of these land snail species have small geographic ranges and that there are many species, make them fascinating subjects for learning about how life on Earth evolved,” Rundell says, adding that “scientists really rely on groups like Pacific island land snails to tell life’s story.”

That opportunity, however, is at risk. “We are losing snail species at an astronomical rate,” Rundell says, “one that is equivalent to, if not exceeding, the worldwide rate of loss of amphibians.” Most species have extremely limited ranges, making them, as she puts it, “particularly susceptible to human-induced extinction.”