Some plants have evolved the capacity to increase estrogen levels in animals that consume them as a defense mechanism to lower male sperm counts and control animal populations.

“that one of the reasons why some plants have evolved this capacity to increase estrogen levels in animals that smoke not smoke it but then animals that consume them [...] plants have figured out ways they've adapted ways to push back on populations of rodents and other species of animals that eat them so plants are engaged in a kind of plant to animal Warfare where they increase the estrogen of the males in that population to lower the sperm counts to keep those populations clamped at certain levels so that those plants can continue to flourish”