Here's why:
* Tiny joeys: Tasmanian devil joeys are born incredibly small, about the size of a grain of rice.
* Limited teats: The mother only has four teats, so only four joeys can survive.
* Competition: The other joeys compete for the limited resources, and the weaker ones usually don't survive.
So, even though a Tasmanian devil mother can give birth to a large litter, only a few will make it to adulthood.