Digestion
Specialised behaviours
#### Specialised behaviours

[Regurgitation](/wiki/Regurgitation_%28digestion%29 "Regurgitation (digestion)") has been mentioned above under abomasum and crop, referring to crop milk, a secretion from the lining of the crop of [pigeons and doves](/wiki/Columbidae "Columbidae") with which the parents feed their young by regurgitation.

Many [sharks](/wiki/Physical_characteristics_of_sharks "Physical characteristics of sharks") have the ability to turn their stomachs inside out and evert it out of their mouths in order to get rid of unwanted contents (perhaps developed as a way to reduce exposure to toxins).

Other animals, such as [rabbits](/wiki/Rabbits "Rabbits") and [rodents](/wiki/Rodents "Rodents"), practise [coprophagia](/wiki/Coprophagia "Coprophagia") behaviours – eating specialised faeces in order to re\-digest food, especially in the case of roughage. Capybara, rabbits, hamsters and other related species do not have a complex digestive system as do, for example, ruminants. Instead they extract more [nutrition](/wiki/Nutrition "Nutrition") from grass by giving their food a second pass through the [gut](/wiki/Gut_%28anatomy%29 "Gut (anatomy)"). Soft faecal pellets of partially digested food are excreted and generally consumed immediately. They also produce normal droppings, which are not eaten.

Young elephants, pandas, koalas, and hippos eat the faeces of their mother, probably to obtain the bacteria required to properly digest vegetation. When they are born, their intestines do not contain these bacteria (they are completely sterile). Without them, they would be unable to get any nutritional value from many plant components.


What are some alternative ways young elephants, pandas, koalas, and hippos can obtain bacteria for proper digestion?