Girl humans tend to go all gooey when a guy loves his mama — like tipping well, it’s an indicator of good boyfriend material. Girl orcas, though, might just sneer and say “oh, of course you’re nice to your mom. You’re just trying to not die.” A new long-term study of about 600 orcas showed that orcas are the ultimate mama’s boys — when male orcas’ mothers die, their own chances of survival drop sharply.

ScienceNow explains:

Young males were three times more likely to die the year after their mother’s death than were males whose mothers were still around. Males over 30 years old were even more vulnerable: Their risk of death increased more than eightfold, Croft and his colleagues report today in Science. Young daughters did just fine after losing their moms, but older daughters were 2.7 times more likely to die.

Like humans, killer whale ladies stick around well after their childbearing years are over, getting all matriarchal. Most orcas are finished having babies by their 40s, but they can live to be as old as 90, doting on their grandbabies. And it’s a good thing, too. Because apparently male orcas need their mommies so badly that if the old biddies weren’t so tough, the species would be even more endangered than it is now.

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