Here's why:
* Sexual dimorphism: Kangaroos exhibit sexual dimorphism, meaning there are distinct physical differences between males and females. This is common in many animal species.
* Size difference: Male kangaroos can be twice the size of females. They have larger heads, thicker necks, and heavier bodies.
* Purpose of size difference: The larger size of males is likely an evolutionary adaptation to help them compete for mates and defend their territories.
So, if you see a big kangaroo, it's most likely a male!