Predator and prey is a relationship that works in the wild. But for whom do we root?

Last summer I studied a dragonfly emerging from its nymph stage on the side of wooden post. I spent 40 minutes documenting with my camera its slow emergence from a thin shell. Its tail started out much shorter than its final, slim length. Its wings, at first brown, moist and squishy-looking, unfurled. They seemed to inflate, then thin, eventually becoming transparent.

Hundreds of shots later, when the insect looked like an adult dragonfly, it climbed to the top of the post and spread its wings. To get a better look at it I shifted position with difficulty, because I had been crouched in the same position for 40 minutes. A few seconds later it took flight, moving faster than I could capture.

Then something happened that I (and maybe the dragonfly) didn't see coming: A fraction of a second after the insect launched, a cedar waxwing swooped down on it.

I was stunned.

To go through all of that, only to become a bird's meal? I'm not 100% sure the bird caught the dragonfly, but they were there, and then before I could blink, they were both gone. I'm not naive about nature. I've witnessed plenty of blitz attacks. But this one really got to me, I guess because I had invested so much time in that insect.

Then I had another realization. Had I been photographing the cedar waxwing, I would have been thrilled to catch it nabbing a dragonfly in flight.

All of that got me thinking: What determines which critter we root for when predators pursue their prey? And why is watching a pursuit and capture so exciting?

"When a hawk catches something, I'm thrilled by it. That's her achieving her greatest ability. ... That's what they're made for," Taylor said.

He talked about a peregrine falcon being the epitome of fitness for its role in the food chain, sometimes flying more than 250 miles per hour (you read that correctly) as it dives to make a kill. That fitness is also true for animals who are the meals, though, Taylor said. They have adaptations that allow them to escape more often than not.

"The peregrine is the top of the food chain and the best there is, but the odds are with the quarry in most cases. Nine times out of 10, that rabbit gets away. Nine times out of 10 that duck or that pheasant gets away from the peregrine," Taylor said.

An animal's fitness for its role can have a learned component, and as he described one example, he gave a case of the defenses of a prey animal. He said that young eagles will head in at a shallow angle when aiming for a jack rabbit; adult eagles have learned that the hares will jump straight up as much as 16 feet, so they know to attack from straight overhead.

Even if we consciously appreciate the natural design of the animals when we witness a chase or attack, we often find ourselves taking sides. What determines whether our allegiance lies with the predator or the prey?

He said he thinks that our protective response extends to cute, furry young ones of other species, and even the adults of such species.

"You look at a small mammal, say, a rabbit. It looks defenseless and cute and fuzzy. I think it's just natural that there's a protective attitude toward those sort of things."

Perhaps that attitude plays a role in what falconer Taylor does when his red-tailed hawk kills a rabbit. "If she plops down and kills a mouse: Eh, no big deal. But when she kills a rabbit I feel empathy for the rabbit, so I move in and make it a quick kill, a humane dispatch," he said.

Which raises another question: Why might we empathize with a bunny and not with a mouse?

Cultural and individual values, and our personal experiences shape our responses, Sweet said. He gave a simple example: Someone who has pet mice or rats might view an animal capturing a rodent with a different attitude than someone who doesn't have personal experience with those species and might tend to think about the damage a mouse or a rat could do.

"If I had a choice between doing work on one species versus another, I had to think about where's the funding going to come from. A project on bald eagles, for example, might be more likely to fly than one on the eastern wood rat. … When I was working with bald eagles, 'Hey, no problem whatsoever! Go for it. Spend all the time you want to.' If I wanted to spend time on the eastern wood rat, you did it, but you didn't make a big deal of it." The Endangered Species Act, he said, never would have passed if the people who crafted and lobbied for it had not carefully chosen the species they used to promote it.

Then there's the question of our attitude toward fish. Do any of us side with them when they're the ones being eaten? Sweet is a birder and wildlife photographer. He recounted a memorable predator-prey sequence involving one fish and three different species of birds. A great blue heron had caught a fish and took to the air with it, only to have it slip out of its beak. A cormorant grabbed the fish, and then an eagle stole it from the cormorant.

So does he, who had an aquarium as a teen, remember at any point hoping the fish would get away? Not really, he said, but he had some empathy. "I thought it was neat that one of the birds would get food, but on the other hand, I thought, 'Boy, that fish has had a rough life.' "

Karen Kraco is a freelance writer and high school science teacher who lives in Minneapolis.