Scientists have discovered that middle aged male killer whales, or orcas, remain dependent on their mothers throughout their lives. Once their mothers die, their risk of death within a year is increased by as much as 14 times. Researchers speculate that this long period of attachment is the result of female whales having a long menopause, almost half of their adult lives females are unable to reproduce. For this reason, mother whales take care of their males for an extended time. Learn more here.