What does the second "athlete" mean? An athlete is like an athlete?
You see it when you watch almost any game: there’s a touchdown, a home run, a goal. An athlete has triumphed! And then, almost instantly they raise their arms over their shoulders, shout aggressively and push out their chest. Like an animal in the wild or, according to a new study, like an athlete not simply winning, but also publicly asserting dominance.
What does the second "athlete" mean? An athlete is like an athlete?

Question

What does the second "athlete" mean? An athlete is like an athlete?
You see it when you watch almost any game: there’s a touchdown, a home run, a goal. An athlete has triumphed! And then, almost instantly they raise their arms over their shoulders, shout aggressively and push out their chest. Like an animal in the wild or, according to a new study, like an athlete not simply winning, but also publicly asserting dominance. 
What does the second "athlete" mean? An athlete is like an athlete?

Answer

The author is comparing athletes with wild animals. Animals hunt and kill. As for athletes, not only do they hunt and kill (their opponents), they also boast about it through their behaviour (putting their arms up, shouting, and pushing our their chests).

Hope this helps
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