Nature’s Babies. Mike Dilger
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hedgehogs become perfect miniature replicas of their prickly parents.
© Wim Weenink/Foto Natura/FLPA
A hedgehog’s prickles, or spines, are actually hollow stiff hairs that can be raised at will if danger threatens.
It’s quite a boast to declare that one is the tallest of all land-living animals, and one which the giraffe is able to make without fear of contradiction. Over thousands of years giraffes have gradually evolved from their shorter-necked ancestors so that today the largest males can reach the dizzying height of 5 m (16 ft) – to the very tips of their horns! The giraffe’s height enables it to browse its favourite food of spiny acacia leaves at levels higher than all the other herbivores are capable of reaching.
In addition to an impressive neck, which incidentally only contains the same number of bones as a human neck (seven), the giraffe possesses long, elegant legs which can produce impressive bursts of speed when necessary and also keep hungry lions at bay with powerful kicks.
Female giraffes associate in small groups whilst the males live either in ‘bachelor’ herds or on their own. The older and larger males tend to mate most of the females in the herd after seeing off any competition through a series of jousts where necks and heads are frequently swung like a wrecking ball-and-chain to assert dominance. The gestation period of the giraffe is long and can last up to 15 months, and the mother gives birth to the single calf standing up. This means that the newborn calf’s entry into the world entails it landing with a terrific thud on the ground below. Within just a few hours the world’s tallest baby is capable of following its mother. This is absolutely essential; there are so many predators on the prowl that the youngster really does have to hit the ground running!
© Andy RouseINHPA
Even the world’s tallest baby has to look up to its mother!
Not only is the Emperor penguin content with being the tallest and heaviest of all living penguins, but it is also the only species tough – or crazy – enough to breed during the Antarctic winter – surely the most challenging environment on earth in which to raise a family.
When temperatures drop to below -40 °C (-40 °F) and polar winds gust at over 190 km/h (120 mph), the only way that these penguins are able to survive during the breeding season is by being very sociable: they crowd together in large groups and thus protect themselves from the elements. These huddles move constantly so that the birds along the colder edge can eventually shuffle into the middle of the group, thereby temporarily exchanging places with the warmer birds in the centre, who must then take their turn on the chilly periphery.
Emperor penguins stay faithful to their mate each breeding season. After an elaborate courtship, the female lays a single, thick-shelled egg, which is then carefully deposited onto the feet of the male to incubate in a special pouch. She then promptly deserts him for two months to feed out at sea. Together with his fellow abandoned males, the male fasts for the entire 65 days of incubation, until the female arrives back to feed the newly-hatched chick on a rich diet of regurgitated fish, krill and squid. It is only then that the half-starved males are allowed to leave and feed out at sea.
To begin with the young chicks are not well insulated and so they must stay sheltered in their mother’s brood pouch for at least 50 days before they join crèches with other youngsters. Here they keep warm by huddling and learning the skills that they will eventually need to survive as breeding adults.
© Frans Lanting/FLPA
‘Brrr! It’s cold out there.’ A baby Emperor peers out on its icy world.
This largest of all living land animals really needs no introduction. With a huge set of ears, a long pair of tusks and a versatile trunk, the African bush elephant is probably the best known and the biggest of all three species of elephant and is also undisputed master of the African savanna.
Female African elephants spend their whole lives in social groups. These consist of the dominant female (matriarch), and an array of immediate family members including mothers, daughters, sisters and aunts. Adult males, on the other hand, lead either solitary lives, or live in loose ‘bachelor’ herds and only join the female unit when one of the herd is sexually receptive. Females ready to mate will seek out the biggest, strongest and oldest bull elephants: these will be the ones who have already asserted their prowess by fighting with and driving away any other potential suitors.
The elephant’s pregnancy is the longest in the natural world and lasts 22 months. At the end of this gestation period, the mother gives birth to a calf weighing up to 120kg (264 lb). The young elephant is born with very few survival instincts and must therefore rely on its elders to teach it everything it needs to know during a prolonged upbringing. All members of the tight-knit female group participate in the care and protection of the newborn calf and it quickly becomes the centre of attention. Since everyone is related, there is never a shortage of babysitters on hand to help, too!
© Martin Harvey/NHPA
Baby elephants are never short of willing playmates.
By choosing a flightless lifestyle, the ostrich has been able to increase its size and weight to such an extent that it is now the world’s largest and heaviest bird. These features, together with their tremendous eyesight, phenomenal running speed and a vicious kick, enable them to protect themselves on the predator-riddled plains of eastern and southern Africa.
In the wild, ostriches are nomadic and will travel long distances in mixed-sex herds with other grazing animals such as zebra and antelope to track down the seeds, plant matter and odd insect which make up their diet. As ostriches lack teeth, they swallow stones to help grind up these tough foodstuffs in their gizzard. Although their wings are not used in flight, they are still large with a wingspan of over 2 m (6 ft 6 in), and male ostriches use them in elaborate mating displays when they compete for territory, social status and the all-important attentions of a small harem of females, or hens.
Once the dominant male has successfully fought off the competition, he will then mate with all of his females. This often leads to many of the hens laying their eggs in the same communal nest, resulting in the production of a clutch of over 30 eggs. Weighing in at 1.5kg (3 lb 5 oz) each, the world’s heaviest eggs are then incubated by the dominant hen and the male until they hatch after about 40 days. The father’s responsibilities do not stop there, as he then assumes sole control of the crèche, in order to both defend the hatchlings and also teach them what to feed on and how to find it.
Zebra
© Friu Polking/FLPA
Until they are able to fend for and defend themselves, ostrich chicks will always stick to safety in numbers.