facts

Once the chick is fully developed it chips its way out of the egg using an "egg-tooth" on the end of its beak. Most penguin chicks take around a day to fully extract themselves from their eggs. Once they emerge from the eggs the chicks are at the mercy of the elements. They have very little protection from the cold or wet, so they rely on their parents for warmth and shelter as well as for food. || Penguins (and other seabirds) DO NOT have a crop!! In fact, not every bird species has one. Crops are mainly found in seed-eating birds. Penguins have an unusually long oesophagus because their stomach is located so low in their bodies, virtually between their knees. The stomach is a big muscular bag that has a glandular lining in the top part (equivalent to the proventriculus) and a folded, muscular part in the bottom. Occasionally penguins swallow little pebbles that might aid their digestion of fish, squid and crustaceans.
 * The eggs are incubated, usually by both parents taking turns, for up to 8 weeks depending on the species - larger penguins lay larger eggs which take longer to incubate. The development of the embryo in the egg follows a similar path to any bird - you will find plenty of examples of the development of chicken eggs in biology textbooks, and for all practical purposes you can consider penguin eggs to follow the same stages (although the timescale of the development will differ).
 * || What a penguin eats, you can find under Biology - Food.

While a penguin has no teeth, the food goes directly to the stomach. Here it is stored either for regurgitation as food for the chicks or for digestion. The liver and pancreas produce the necessary elements to aid the digestion. The pancreatic juice delivers, among other functions, bicarbonates for the regulation of the acidity in the stomach and supplies enzymes for digestion. From here the almost digested food goes to the intestines, where all rest-material are extracted and this leaves the body through the cloaca.

Recent research by French scientists has shown that king penguins, for example, can adjust the PH (acidity) of their stomach to prevent rapid digestions. Another study, also by French scientists, showed that king penguins use bacteria in their stomachs that prevent the food from digestion! || Females lay a single egg onto their feet and transfer it immediately to the male who incubates it on his feet underneath a fold of abdominal skin, throughout the Antarctic winter. Temperatures can drop as low as -70°C but they stick with the task! ||  ||   || Erect-crested penguin population trends are decreasing, ||