Here is a general range of gestation periods for different groups of mammals:
1. Humans (Homo sapiens): Around 37-40 weeks (approximately 9 months)
2. Elephants (Loxodonta africana/Elephas maximus): Approximately 22 months (the longest gestation period among all mammals)
3. Baleen whales (e.g., Blue whale): Around 10-12 months
4. African bush elephant: Around 22 months
5. Giraffes (Giraffa camelopardalis): Approximately 15 months
6. Chimpanzees (Pan troglodytes): Around 8 months
7. Dogs (Canis lupus familiaris): Approximately 63 days
8. Cats (Felis catus): Around 63-65 days
9. Rabbits (Oryctolagus cuniculus): Around 30-32 days
10. Mice (Mus musculus): Around 20-22 days
11. Guinea pigs (Cavia porcellus): Around 63-72 days
12. Horses (Equus caballus): Approximately 11 months
13. Cows (Bos taurus): Around 279-285 days
14. Sheep (Ovis aries): Around 145-155 days
15. Pigs (Sus scrofa domesticus): Approximately 115 days
It's worth noting that gestation periods can vary within a species due to genetic factors, environmental conditions, maternal health, and other individual differences.