Intense competition for access to females (Eldridge and Coulson 2015)
Assessment of female reproductive state
Protection of joey
Newborn and pouch young (kangaroos, general, unless otherwise noted)
Poor nutrition (Dawson 2013, except as noted)
Parasites (non-comprehensive list)
As a kangaroo joey grows, the nutrients in its mother's milk change.
Image credit: © Luke Shelley at Flickr. All rights reserved. Used with permission from the artist.
Image location: Kangaroo Island, Australia