Broiler chickens, in particular. The broiler chicken is the most popular breed of chicken produced by modern humans. If you go to a supermarket in any modern country, and see a chicken (dead, though living chickens are a thing too), it's probably broiler chicken.
Humans make lots of broiler chickens. 23 billion are alive at any instant, and each lives about 40 days (they grow extremely fast).
From
ScienceDaily:
These chickens are an artificially evolved new 'morphospecies', the kind of thing palaeontologists recognise, that reflect a biosphere unrecognisable from its pre-human state and now dominated by human consumption and resource use.
"Since domestication there have been many strange and beautiful chicken breeds, but the broiler is perhaps the most extreme form of all. The body shape, bone chemistry and genetics of the modern meat chicken is unrecognisable from wild ancestors and anything we see in the archaeological record."
It usually takes millions of years for evolution to occur, but here it has taken just decades to produce a new form of animal that has the potential to become a marker species of the Anthropocene -- and the enormous numbers of these chicken bones discarded worldwide means that we are producing a new kind of fossil for the future geological record.