Search results
Results from the WOW.Com Content Network
This is a collection of lists of mammal gestation period estimated by experts in their fields. The mammals included are only viviparous (marsupials and placentals) as some mammals, which are monotremes (including platypuses and echidnas) lay their eggs. A marsupial has a short gestation period, typically shorter than placental.
In the latter, the eggs develop in utero for about 28 days, with only about 10 days of external incubation (in contrast to a chicken egg, which spends about one day in tract and 21 days externally). [11] After laying her eggs, the female curls around them. The incubation period is divided into three phases.
The duration of this period varies between species. For most species, the amount a fetus grows before birth determines the length of the gestation period. Smaller species normally have a shorter gestation period than larger animals. [2] For example, a cat's gestation normally takes 58–65 days while an elephant's takes nearly 2 years (21 ...
Gestation, called pregnancy in humans, is the period of time during which the fetus develops, dividing via mitosis inside the female. During this time, the fetus receives all of its nutrition and oxygenated blood from the female, filtered through the placenta , which is attached to the fetus' abdomen via an umbilical cord .
Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). [1] It is typical for mammals, but also occurs for some non-mammals. Mammals during pregnancy can have one or more gestations at the same time, for example in a multiple birth. [2]
Cape robin-chat (at right) feeding a red-chested cuckoo parasite chick. The Cape robin-chats are monogamous and highly territorial nesters. [19] A pair's territory usually comprises some fraction of a hectare, but its extent varies considerably depending on the habitat. [18] The nest site is within 5 feet (regularly 0 – 2 feet) from the ground.
Very precocial birds can be ready to leave the nest in a short period of time following hatching (e.g. 24 hours). Many precocial chicks are not independent in thermoregulation (the ability to regulate their body temperatures), and they depend on the attending parent(s) to brood them with body heat for a short time. Precocial birds find their ...
Ligon (1999) suggested with Vehrencamp (2000) that male incubation existed first and later gave way to shared and finally female only incubation. A possible evolutionary timeline by Kavanau suggests that basal theropod dinosaurs evolved into birds that evolved unique bi-parental care, after which avian birds evolved homeothermy and flight.