Giraffes are the tallest mammals on Earth, with their legs
alone are taller than many humans at about 6 feet. Not only that, they give birth
standing up, with their young falling more than 5 feet to the ground at birth!
Now that’s a way to say hello to the world... by smacking into it! :p
Male giraffes are ready to mate around the age of 6 however
due to the way in which the stronger, more mature bulls get to mate first, it’s
not uncommon to see them in their double digits before they have a chance to
charm a lady. Alternatively females are ready to mate around the age of 4.
Typically giraffes will go into estrous during a rainy season
when food is abundant and stress is low. The estrous cycle for a giraffe is around 14.7
days with regular ovarian cycles prior to conception. Adult males tend to
associate, and sexually investigate, females when they are cycling. Males will
taste the urine of a female to judge how much estrus is in their urine and
whether they are ready for mating. The courting rituals include gentle rubbing
of their necks on each other.
The conception time is approximately 15 months, with cows
only having one calf at a time. The mother stands while in labour and delivers
her calf standing up, with it falling several feet. The thick sac protecting
the calf at birth prevents it from being harmed. The offspring can weigh up to
70kg and stand 6 feet tall when born.
Unfortunately the presence of a calf acts as a threat to the
herd, attracting more predators than usual. It’s because of this that only a
quarter of the calves make to do adulthood. Young giraffe feed off the milk of
their mother for the first year but they will feed from grass and low lying
leaves from tree at around the two month mark.
FUN FACT! A giraffe's feet are the size of a dinner
plate—approximately 12 inches across. Females use their hooves as weapons to
protect their young. They are strong enough to kill a lion, the giraffe's only
predator aside from humans.
Juvenile and two adults
Anonymous
Giraffe’s running
Anonymous
Reference
Bercovitch, F.B., Bashaw, M.J. & del Castillo, S.M.
2006, "Sociosexual behavior, male mating tactics, and the reproductive
cycle of giraffe Giraffa camelopardalis", Hormones and Behavior, vol. 50, no. 2, pp. 314-321.
A big wake-up call for a baby giraffe indeed! While you go into good detail on the reproductive cycle, I’m intrigued in learning more about the mating process of this species. Given their large size and rather gangly appearance, I imagine that mating must be quite difficult! How do giraffe manage this process? Why do females birth standing upright? What are evolutionary mechanisms that have resulted in this behaviour?
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