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Nature’s toughest mothers make 'ultimate sacrifice' Nature’s toughest mothers make 'ultimate sacrifice'
(1 day later)
By Anna-Louise Taylor BBC Nature NewsBy Anna-Louise Taylor BBC Nature News
Some animal mothers pay with their lives in order to ensure the survival of their offspring, while others have to endure extreme parenting situations. What must they go through?Some animal mothers pay with their lives in order to ensure the survival of their offspring, while others have to endure extreme parenting situations. What must they go through?
Stories of young animals fighting for survival around the world are being filmed in May for the BBC programme Planet Earth Live.Stories of young animals fighting for survival around the world are being filmed in May for the BBC programme Planet Earth Live.
Baby elephants in Kenya, black bears in Minnesota, toque macaques in Sri Lanka, meerkats in South Africa, gray whales in the Pacific and the lions of the Masai Mara are some of the animals being followed by Natural History Unit crews.Baby elephants in Kenya, black bears in Minnesota, toque macaques in Sri Lanka, meerkats in South Africa, gray whales in the Pacific and the lions of the Masai Mara are some of the animals being followed by Natural History Unit crews.
The mothers of the youngsters are fiercely protective of their children, doing whatever they can to help them grow, just like other mothers in the animal kingdom.The mothers of the youngsters are fiercely protective of their children, doing whatever they can to help them grow, just like other mothers in the animal kingdom.

Full-time jobs

Full-time jobs

African elephants have a tough pregnancy; they carry their babies for 22 months before giving birth.African elephants have a tough pregnancy; they carry their babies for 22 months before giving birth.
This gestation period is the longest of any animal.This gestation period is the longest of any animal.
But orangutans look after their children for longer than any other primates, except humans.But orangutans look after their children for longer than any other primates, except humans.
It takes about nine years for them to teach their young everything they need to know to survive in the forest.It takes about nine years for them to teach their young everything they need to know to survive in the forest.
Much of the knowledge that is passed down involves food - how to find, fish for and eat ants and termites, how to identify edible plants, and, perhaps more importantly, the inedible or poisonous ones.Much of the knowledge that is passed down involves food - how to find, fish for and eat ants and termites, how to identify edible plants, and, perhaps more importantly, the inedible or poisonous ones.
All orangutans need to know how to build a secure nest, and how to take shelter from rain.All orangutans need to know how to build a secure nest, and how to take shelter from rain.
They may live for up to 50 years, and each mother passes the knowledge on to her young.They may live for up to 50 years, and each mother passes the knowledge on to her young.

Giving up sleep

Giving up sleep

Full-time parenting also involves full-time vigilance.Full-time parenting also involves full-time vigilance.
Killer whale and bottlenose dolphin calves do not sleep for a whole month after they are born, and therefore, neither do their mothers.Killer whale and bottlenose dolphin calves do not sleep for a whole month after they are born, and therefore, neither do their mothers.
A team from the University of California examined the sleeping patterns of captive killer whales (Orcinus orca) and bottlenose dolphins (Tursiops truncates), and found that the "exceptional wakefulness of newborn whales and dolphins has no ill-effect on their development".A team from the University of California examined the sleeping patterns of captive killer whales (Orcinus orca) and bottlenose dolphins (Tursiops truncates), and found that the "exceptional wakefulness of newborn whales and dolphins has no ill-effect on their development".
Their study showed that killer whales and bottlenose dolphins, and their mothers, avoided obstacles, swam continuously and repeatedly surfaced for air 24 hours a day for the first month.Their study showed that killer whales and bottlenose dolphins, and their mothers, avoided obstacles, swam continuously and repeatedly surfaced for air 24 hours a day for the first month.
The duration of the cetaceans' rest is gradually increased until it "reaches normal adult levels" over several months.The duration of the cetaceans' rest is gradually increased until it "reaches normal adult levels" over several months.

class="section-header" id="heading-3">The 'ultimate sacrifice'

The 'ultimate sacrifice' href="http://www.bbc.co.uk/nature/life/Caecilian#p006fcfx" >Link
Some animals sacrifice themselves for motherhood, allowing their young to commit matricide.Some animals sacrifice themselves for motherhood, allowing their young to commit matricide.
Black lace-weaver spider (Amaurobius ferox) mothers sacrifice themselves to feed their cannibalistic young.Black lace-weaver spider (Amaurobius ferox) mothers sacrifice themselves to feed their cannibalistic young.
A clutch of 60-130 spiderlings first feed on unhatched eggs, first eating their brothers and sisters before turning on their mother and devouring her.A clutch of 60-130 spiderlings first feed on unhatched eggs, first eating their brothers and sisters before turning on their mother and devouring her.
She could flee the web and avoid certain death, but instead encourages her spiderlings onto her body, giving them the nutrients they need to grow.She could flee the web and avoid certain death, but instead encourages her spiderlings onto her body, giving them the nutrients they need to grow.
After she has died, the spiderlings stay together as a group for 3-4 weeks and go hunting, until they leave the nest.After she has died, the spiderlings stay together as a group for 3-4 weeks and go hunting, until they leave the nest.
Parasitic mites known as Adactylidium are also devoured by their children, in a bizarre four day life cycle.Parasitic mites known as Adactylidium are also devoured by their children, in a bizarre four day life cycle.
The mites live by feeding on another insect's egg, growing daughters in their body along with one son. This single male actually mates with his siblings while they are all still inside their mother. The impregnated females then emerge, along with the male, who dies just a few hours later.The mites live by feeding on another insect's egg, growing daughters in their body along with one son. This single male actually mates with his siblings while they are all still inside their mother. The impregnated females then emerge, along with the male, who dies just a few hours later.

id="heading-4">Putting on weight

id="heading-3">Putting on weight

Some animal mothers must put on vast amounts of weight to ensure they have successful pregnancies.Some animal mothers must put on vast amounts of weight to ensure they have successful pregnancies.
Polar bears, for example, must put on about 200kg (400lbs) from eating seal blubber, before they can actually get pregnant.Polar bears, for example, must put on about 200kg (400lbs) from eating seal blubber, before they can actually get pregnant.
The excess weight allows them to fast for eight months and provide fat-rich milk for their cubs once they are born.The excess weight allows them to fast for eight months and provide fat-rich milk for their cubs once they are born.

id="heading-5">Sharing skin

id="heading-4">Sharing skin

Providing food for their newborn remains a top priority for any mother, but a caecilian mother will feed its young with its own skin, which is rich in fat.Providing food for their newborn remains a top priority for any mother, but a caecilian mother will feed its young with its own skin, which is rich in fat.
The young, which have small baby teeth, increase their weight by ten times in one week.The young, which have small baby teeth, increase their weight by ten times in one week.
They do this by drinking a secretion from their mother, swarming all over her in a frenzy and ripping her skin away.They do this by drinking a secretion from their mother, swarming all over her in a frenzy and ripping her skin away.
The mother regrows her skin every three days to provide her young with another nourishing meal.The mother regrows her skin every three days to provide her young with another nourishing meal.
Another animal which shares its skin with its young is the Surinam toad, which lives in South America.Another animal which shares its skin with its young is the Surinam toad, which lives in South America.
The female lays her eggs on the male's belly, which he fertilises then rolls in to pouches in the skin on her back.The female lays her eggs on the male's belly, which he fertilises then rolls in to pouches in the skin on her back.
The young bypass the larval stage, and emerge from the pockets on their mothers back, fully formed.The young bypass the larval stage, and emerge from the pockets on their mothers back, fully formed.
This reproduction method ensures all of the toad's fertilised eggs survive.This reproduction method ensures all of the toad's fertilised eggs survive.