Incubation is the process by which certain oviparous animals hatch their eggs. Multiple and various factors are vital to the incubation of various species of animal. In many species of reptile for example, no fixed temperature is necessary, but the actual temperature determines the sex ratio of the offspring. In birds in contrast, the sex of offspring is genetically determined, but in many species a constant and particular temperature is necessary for successful incubation. In poultry, the act of sitting on eggs to incubate them is called brooding; the action or behavioral tendency to sit on a clutch of eggs is called broodiness, most egg-laying breeds of poultry have had this behavior selectively bred out of them to increase production. A wide range of incubation habits is displayed among birds. In warm-blooded species such as bird species body heat from the brooding parent provides the constant temperature, though several groups, notably the megapodes, instead use heat generated from rotting vegetable material creating a giant compost heap while crab plovers make partial use of heat from the sun.
The Namaqua sandgrouse of the deserts of southern Africa, needing to keep its eggs cool during the heat of the day, stands over them drooping its wings to shade them. The humidity is critical, because if the air is too dry the egg will lose too much water to the atmosphere, which can make hatching difficult or impossible; as incubation proceeds, an egg will become lighter, the air space within the egg will become larger, owing to evaporation from the egg. In the species that incubate, the work is divided differently between the sexes; the most common pattern is that the female does all the incubation, as in the Atlantic canary and the Indian robin, or most of it, as is typical of falcons. In some species, such as the whooping crane, the male and the female take turns incubating the egg. In others, such as the cassowaries, only the male incubates; the male mountain plover incubates the female's first clutch, but if she lays a second, she incubates it herself. In hoatzins, some birds help their parents incubate broods.
The incubation period, the time from the start of uninterrupted incubation to the emergence of the young, varies from 11 days to 85 days. In these latter, the incubation is interrupted. In general smaller birds tend to hatch faster, but there are exceptions, cavity nesting birds tend to have longer incubation periods, it can be an energetically demanding process, with adult albatrosses losing as much as 83 g of body weight a day. Megapode eggs take from 49 to 90 days depending on the ambient temperature. In other birds, ambient temperatures can lead to variation in incubation period; the egg is incubated outside the body. However, in one recorded case, the egg incubation occurred within a chicken; the chick hatched inside and emerged from its mother without the shell, leading to internal wounds that killed the mother hen. Embryo development remains suspended until the onset of incubation; the freshly laid eggs of domestic fowl and several other species can be stored for about two weeks when maintained under 5 C.
Extended periods of suspension have been observed in some marine birds. Some species begin incubation with the first egg; some start to incubate after the last egg of the clutch. Incubation periods for birds Very few mammals lay eggs. In the best known example, the platypus, the eggs develop in utero for about 28 days, with only about 10 days of external incubation. After laying her eggs, the female curls around them; the incubation period is divided into three phases. In the first phase, the embryo relies on the yolk sac for sustenance; the yolk is absorbed by the developing young. During the second phase, the digits develop. In the last phase, the egg tooth appears; the only other egg-laying mammal is the echidna. New science research has been found that eggshells have a nanostructure that has inner and outer layers; the structure of this shell contains a protein known as osteopontin, found in tooth and bone. What researchers found was that the inner layers of the shell were thinner than the outer shells.
This is because in the process of the egg being incubated the chicken embryos are taking the protein from the shell making the chicks skeleton stronger. Methods of incubation vary among the many different kinds of reptiles. Various species of sea turtles bury their eggs on beaches under a layer of sand that provides both protection from predators and a constant temperature for the nest. Snakes may lay eggs in communal burrows, where a large number of adults combine to keep the eggs warm. Alligators and crocodiles either lay their eggs in mounds of decomposing vegetation or lay them in holes they dig in the ground. Fish do not incubate their eggs. However, some species mouthbrood their eggs; some amphibians brood their eggs. The female salamander Ensatina curls around the clutch of eggs and massages individual eggs with her pulsating throat; some aquatic frogs such as the Surinam toad have pouches in their skin into which the eggs are ins
Media Take Out is a blog-style gossip website focused on entertainment and celebrity news involving African Americans topics and celebrities. The website was founded by a former corporate lawyer. Mwangaguhunga was born to Ugandan parents in Washington, D. C. is a graduate of John Jay College of Criminal Justice at the City University of New York, received two degrees from Columbia University. Exclusives have been quoted by Good Morning America, Watch What Happens Live, The New York Times, BET Style, MTV News, the "Page Six" column of the New York Post, by radio personalities including Wendy Williams, Howard Stern, Tom Joyner. Media Take Out has broken several stories, including Kim Kardashian's first pregnancy, Remy Ma's criminal charges and Michael Jordan's divorce. Mwangaguhunga has stated, "We get 90% of our stories from insiders looking to spill the beans like hairstylists, bodyguards or bitter ex-girlfriends". MediaTakeOut.com MediaTakeOut.com one of the Top 50 Black Owned Websites NY TIMES: A Gossip Site Finds Its Niche VICE: Meet The Lawyer Who Runs Media Take Out Media Take Out.com Dishin the Dirt on African American Celebs: But Skeptics say It's All Lies NPR Interviews owner Mediatakeout
The Bevan point, named after Benjamin Bevan, is a triangle center. It is defined as center of the Bevan circle, the circle through the centers of the three excircles of a triangle; the Bevan point M of triangle ABC has the same distance from its Euler line e as its incenter I and the circumcenter O is the midpoint of the line segment MI. The length of MI is given by | M I | = 2 R 2 − a b c a + b + c where R denotes the radius of the circumcircle and a, b and c the sides of the triangle ABC; the Bevan is point is the midpoint of the line segment NL connecting the Nagel point N and the Longchamps point L. The radius of the Bevan circle is 2R, twice the radius of the circumcircle. Eric W. Weisstein. Bevan Point. From MathWorld--A Wolfram Web Resource Alexander Bogomolny. Bevan's Theorem at cut-the-knot Encyclopedia of Triangle Centers. X = BEVAN POINT