Mammals reproduce sexually, via the union of sperm and egg cells. Except for five species of egg-laying mammals, called monotremes, all mammals give birth to live young.Know More
Mammals possess two main types of cells: somatic cells and sex cells. Somatic cells account for most of the body's cells and are responsible for growth, repair and healing. Sperm and egg sex cells contain one set of chromosomes each and fuse during sexual reproduction to form a zygote that later develops into an embryo and then a fetus. In most mammals, the fetus develops in the uterus until it is able to survive outside the mother's body. In the pouched mammals, called marsupials, offspring are born very early and finish development in the female's pouch. A placenta forms in some species of marsupials, while a simple yolk sac delivers vital nutrients in others.
Five species of mammals, called monotremes, actually lay eggs. Monotremes, including the duck-billed platypus and four species of echidna, are all native to Australia and New Guinea. Like birds, monotremes possess a cloaca, which is a single orifice that serves for both reproduction and excretion. The eggs receive nourishment from the female's body for a few weeks before they are laid. Like other mammals, monotremes have mammary glands and feed their young milk.Learn more about Animal Reproduction
Pigeons, like most other birds, reproduce by laying fertilized eggs and waiting for them to hatch.The pigeon mating and fertilizing process is similar to that of other birds with the male mounting the female. Full Answer >
Reproduction in mollusks can be sexual depending on the species. All species produce eggs; in most species, eggs are released from the female's body before fertilization. The simplest mollusk reproductive system relies on this kind of external fertilization.Full Answer >
Camels reproduce by copulating during breeding season after the males compete for dominance. After a gestation period of 12 to 14 months, the female gives birth to a calf that weighs up to 80 pounds and that can stand and walk a short time after being born.Full Answer >
Zebras reproduce sexually: The male zebra, which is called a stallion, mounts a female zebra, which is called a mare, and deposits sperm in the mare's vagina via the stallion's penis. If the mating is successful, the mare births a single foal 12 to 13 months later.Full Answer >