Yes, caribou and reindeer are the same species, Rangifer tarandus, but they have different names depending on where they live and whether they are domesticated:
North America
In North America, wild animals are called caribou, while domesticated animals are called reindeer.
Eurasia
In Eurasia, all animals are called reindeer.
Caribou vs reindeer: 4 Main Differences Explained - A-Z Animals
Caribou and reindeer are members of the deer family and are herbivores that mostly eat lichen, a combination of algae and fungi. Their appearance can vary depending on their diet, environment, and selective breeding.
There are several subspecies of caribou, including:
Barren-ground caribou (Rangifer tarandus granti)
Svalbard caribou (R.t platyrhynchus)
European caribou (R.t. tarandus)
Finnish forest caribou (R.t. fennicus)
Greenland caribou (R.t. groenlandicus)
Woodland caribou (R.t. caribou)
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Yes, most female caribou have antlers, making caribou the only deer species where both sexes grow them:
Antler growth
Antlers are shed and regrown annually. Antler development is out of phase by 3–6 months between the sexes. Male antlers start developing in March, grow rapidly in May–July, and are fully hardened by mid-September. Female antlers develop from June–September and are fully hardened by late September.
Antler shedding
Antlers are shed at different times of the year depending on age and pregnancy status:
Male caribou: Adult males shed their antlers in late fall, usually in November, after the rut. Younger males may retain their antlers until April.
Female caribou: Pregnant females lose their antlers a few days after giving birth in June. Barren cows shed their antlers before spring.
:: Male antlers start developing in March, grow rapidly in May–July, and are fully hardened by mid-September. ::
Just like the human male at the age of 70.