“I don’t know anybody who actually agrees with me,” he said with a frank smile.

“Even my own students aren’t there yet.”

To grasp his view, a little bit of history is in order. Darwin famously proposed the idea of evolution by natural selection, what is often called survival of the fittest. To put it simply, living things vary in their inherited traits, from speed to color to sense of smell. The traits of the individuals who survive longer and have the most offspring become more common. So, over time, the faster antelope have more young, the fastest of them have more offspring, and antelope end up very speedy.

But reproduction isn’t just about surviving and staying healthy long enough to mate. You have to find a mate. And in many species, your mate must choose you. This process is sexual selection. Female birds are often the ones choosing. And their choices can produce male birds that are incredibly colorful, and some that are elaborate dancers or designers of striking boudoirs — like the bower birds. If, for example, females like males with long tails, then long-tailed males have more offspring, and the longest-tailed of those offspring reproduce more. In the end, that species becomes known for its long tails.

Maydianee Andrade, an evolutionary biologist and vice dean at the University of Toronto, Scarborough, who studies sexual selection and teaches evolution, said that “the question is basically this. You can think of females when they are choosing a mate as foraging. So what are they looking for?”

“If you’re dragging a giant tail behind you, that might tell the female something,” she said. “A male that survives carrying a large heavy tail is more impressive than a male that survives with a short tail.”