Two Western Grey Kangaroos born at Brookfield Zoo have
been spending time outside their mothers’ pouches exploring their outdoor
habitat. The young Kangaroos, called joeys, were born on February 20 and March
13 of last year to moms Daisy, 7½, and Sheila, 11.

Photo Credit: Jim Schulz/Chicago Zoological Society
 

The 10- and 11-month-old joeys only recently began hopping
around and exploring their surroundings. They spent the first several months of
life tucked into their mothers’ pouches, where they nursed and grew.  They will continue to nurse until they are 18
months old.  Of course by then, they’ll
no longer be able to fit in the pouch.

At birth, a joey is extremely underdeveloped and is about
the size of a jellybean. During this early stage of development, a mother
produces low-fat milk for her young, and as a joey gets older and ventures out
of the pouch, the milk becomes high in fat. A truly amazing attribute of this
species is that if a mother Kangaroo is nursing a newly born joey and a
juvenile already out of the pouch, she has the ability to produce both low-fat
milk and high-fat milk at the same time.

Western Grey Kangaroos are one of 60 species of Kangaroos
and Wallabies, all of which are native to Australia.