(of an organism or tissue) living in the absence of air or free oxygen. pertaining to or caused by the absence of oxygen.
Parakeets can breed year round if conditions are right in their environment. Normal breeding season begins early in the year and continues until fall. It is very rare to see parakeets mating, but a male and a female must mate to keep the eggs fertile.
Snapping turtles mate between April and November, and are most active in breeding during warmer months. They begin courtship by facing one another and moving their heads from side to side. Mating begins with the male mounting the female and adjusting his tail beneath the female's to allow the cloacal openings to touch. A female snapping turtle may keep viable sperm in her body for several years, so that eggs are fertilized even in years when she does not mate.