No, birds don’t get “pregnant” like mammals do. The term “pregnancy” usually involves having a true uterus – an organ that carries and nurtures developing babies inside of the mother’s body. Also, pregnancy ends with the birth of live offspring....
In placental mammals, the gene SRY (Sex-determining Region Y) is a key factor that determines the forma- tion of testes (the Testis Determining Factor, TDF) and is located on the Y chromosome5,6. In most placental mammals, the X and Y chromosomes contain short homologous regions (...
Amphibian reproduction has more in common with that of fish than it does of mammals or even reptiles. While all of these animals reproduce sexually (meaning that the species consists of males and females and mating involves the fetilization of eggs by sperm), reptiles and mammals reproduce throu...
Are all Australian mammals marsupials? Why do marsupials produce immature babies? Why don't marsupials get rabies? How do dingoes survive? How long do marsupials live? Are any marsupials carnivores? How do dingoes reproduce? Why are marsupials and monotremes only found in Australia? What animals...
How do melosis and sexual reproduction (fertilization) produce offspring that differ genetically from the parents? How do placental mammals reproduce? How do plants reproduce? How does asexual reproduction by spores occur in plants? How did sexual reproduction evolve from asexual, unicellular organisms...
Cells The cells are oxidized through an enzymatic processes, and the oxidation is the source of energy for humans and most other mammals. Oxygen is needed to build new cells and tissue, replace old tissue, dispose of waste material and reproduce more cells. ...
What do ticks eat? Females and males of most species feed on blood of mammals, birds, and reptiles. Each species does have a preferred host, although most will feed on whatever blood is available to them. Thus, ticks are known to bite: Cats and Dogs Deer Humans Livestock What is the ...
Superfetation is known to promote polyandry in some mammals because sequential litters can be fathered by different males38. We predicted, and found, that the evolution of superfetation is associated with the evolution of placentation34. A consequence of superfetation in Poeciliinae is that ...
Louis Bolk suggested that all mammals have the ability to express the traits we call atavisms, but humans just don't. This wouldn't make atavisms evolutionary throwbacks, just a genetic fluke. What is an Atavism? Four-year-old Jiaxue, of China, was born with hairy black moles covering ...
So how do eels reproduce, and where do they do it? Lucy Cooke digs into the ancient mystery. [Directed by Anton Bogaty, narrated by Adrian Dannatt, music by Jarrett Farkas]. science education animals evolution biology history sex TED-Ed animation oce...