Red kangaroo unusual ability to delay birth of their baby until their previous Joey has left the pouch. This is called embryonic diapause. Copulation may last 25 minutes. The red kangaroo has the typical reproductive system of a kangaroo. The neonate emerges after only 33 days. Usually only one young is born at a time. It is blind, hairless, and only a few centimetres long. Its hind legs are mere stumps; it instead uses its more developed forelegs to climb its way through the thick fur on its mother's abdomen into the pouch, which takes about three to five minutes. Once in
Heermann's kangaroo rat range from , and their tail aids in providing counterbalance. Heermann's kangaroo rat has a wide window in which it primarily breeds, ranging from February to October. Its highest breeding activity is in April, and this decreases in July. Heermann's kangaroo rat rarely show increased levels of sexual behavior. Copulation is rather quick, and typically only lasts a couple seconds. If the animals are caged, the rats show no increase in sexual behavior. Females rats will even show aggression if her genitalia are swollen and enlarged. During labor, the female rat will assist the delivery of the young with her