Environmental Science Research

There’s a lot to learn from the diversity of animal behavior, and Professor Hope Klug and her students are going straight to the source.

by Shawn Ryan

AAs they do in the world of humans, dads and moms in the non-human world meet, and eventually, babies follow. Dad builds a home for his family. Mom births the babies. 

Then she takes off. Well, OK, maybe that’s not the way things usually work, but dad sticks around with the kids. Unless he eats them.  

OK, slam the brakes. We’re not discussing mating in the anthropological (humankind) world here. 

Hope Klug, UC Foundation associate professor in the college of Arts and Sciences, Department of Biology, Geology and Environmental Science, says this is the way the sand goby fish species mates, breeds and carries on. “It’s the dad that takes care of the eggs and he builds this lovely nest. Then he provides the parental care to his eggs until they hatch. And he’ll also eat some of them.” 

“We think we can take what we learn from studying these small animals and make inferences about what’s likely going on in mammals or, in some cases, potentially even humans,” Klug says.

For years, Klug has researched the mating habits of fish and insects, in general, trying to understand why animals behave the way they do from an evolutionary perspective. How do they meet? Why do they mate in their particular way? And yes, why do some consume their own children? “What my students and I want to know is: Why do we see the amazing diversity in animal behavior that we see in nature?” Klug says. “Why animals vary quite a bit in their meeting strategies. Why they vary quite a bit in parental care.” 

Species that cannibalize their offspring are not that unusual in the world of fish and insects, says Klug, who gave a virtual presentation in February on her area of expertise for an event hosted by The Science & Entertainment Exchange. But cannibal parents are “perplexing,” she says. “If you’re always eating your own babies, you’re not really passing on your own genes,” she explains. 

One long-held supposition is that some species eat their young because there’s a lack of food in their environment. The adults eat their young to give them the energy needed for survival, but research shows that’s not necessarily true, Klug says, pointing to the sand goby. Her research team discovered Dad eats the eggs that are taking the longest to hatch. A male goby only lives a year and breeds only during a six-week season, Klug explains. If he cares for one clutch of eggs and a few still haven’t hatched, he eats those so he can move on, mate again and care for another batch. The more he can mate, the better for the species as a whole. 

So how does understanding what fish do in their mating and parental habits help in a larger sense? in some cases, knowledge gathered there can be used to determine what may happen in other species, Klug says. “We think we can take what we learn from studying these small animals and make inferences about what’s likely going on in mammals or, in some cases, potentially even humans,” she says. 

In the wild, fish and insect parents appear more likely to take care of offspring that need a good deal of care to survive in the first place. In comparison, parents are pretty easygoing on kids who need only a little attention before they can live on their own, she says. “We could take from that, apply it to other species, then try to figure out whether that seems to be what’s going on in mammals.”