BV Earth Ed Guide Online Chapter 5[1]

8/8/2019 BV Earth Ed Guide Online Chapter 5[1]

http://slidepdf.com/reader/full/bv-earth-ed-guide-online-chapter-51 1/12

In the fIlm

is lled with enchanting, intimate, anddramatic scenes in which three o the greatmammals rear and care or their o spring.

shows, in all its intensity, the power o an animal’s instinct to nurture and protectits o spring. From the mother Polar bearignoring her own hunger as she patiently waits

or the right moment to coax her cubs out onthe Arctic sea ice, to the weary and parched

A rican elephant mother on her long trek orwater, turning back along her tracks to urge onthe exhausted cal behind her, to the mother

Humpback urgently slapping her ns on theocean’s sur ace to keep contact with her cal in the stormy waters o a southern ocean. Aswell as this, shows some o the mostengaging and comic behavior ound amongbird species: the elaborate mating displayso the Birds o Paradise and the high-divingantics o Mandarin duck chicks.

lIfe cYcle fActs…

• all living things have a li e cycle, rom thetiniest bacteria to the gigantic Blue whale

• a li e cycle is a series o stages a livingorganism goes through rom its birth toits death

• a li e cycle includes birth, li e as a youngster,adolescence, adulthood, mating, caring oro spring and death

• throughout this cycle, each individual’s aimis to develop, grow and learn enough tosurvive, and pass on its genes to its young

• the li e cycles o many animals are intricatelylinked with the planet’s seasons

Li e Cycles

– Educator’s Guide 46



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the africaN elephaNt

AfrIcAn elephAnt fActs…

• the age at which elephants reach maturityvaries with the environmental conditions

• emale elephants generally become readyto mate when they are about 14 years old,but have been known to mate until theyare nearly 60; males are around 20 be orethey mate

• the peak o breeding is in the rainy seasonthough elephants can breed at any time

• emale elephants have one o the longestpregnancies o the animal world: 22 months

• elephants give birth to a single cal and haveto wait a minimum o 2 to 4 years betweenpregnancies

• calves measure about 3 t. (0.8 - 1.05meters) at the shoulder at birth and weighabout 200-260 lbs (90-120 kg)

• elephants grow to become the biggestanimals on land, and can reach 13 t. (4meters) in height and weigh up to 10 tons

• elephants can live or 70 years

the neWBorn cAlf

Other emales o ten gather around acalving elephant. When the cal is born theysometimes give assistance to the mother asshe uses her eet, trunk and tusks to help thecal stand. Newborn elephant calves try to

stand almost immediately. On average it takesthem about 30 minutes. They are born withtheir eyes open and unctional, and as soonas they are on their eet they search or theirmother’s nipples. A cal ’s mother may bendher legs to help the cal reach her and startsuckling. Elephant calves suckle requently:at least every hour.

When they’re rst born, calves can have poortrunk control and they may be shaky on theirlegs or a ew days but, by the time they’re twodays old, they can usually move with the herd.

the GroWInG cAlf

Elephant calves are entirely dependent ontheir mothers or milk at rst, but they beginplaying with the vegetation they will eventuallyeat – leaves, bark, shrubs and roots – veryearly. They learn about it by investigating andtasting ood taken rom their mother’s mouth,although they don’t actually swallow any grassuntil they’re about our months old.

Elephant calves have to learn everything romeating grass to how to drink water using theirtrunk. It can take up to six months or a cal tolearn how to use its trunk to bring water up toits mouth. By six months, elephant calves areeating a signi cant amount o vegetation, and,by the time they’re two years old, they spendas much o their time eating as the adults do.

They continue suckling until they’re at leasttwo years old, but a ter six months they do it




less o ten. I a cal loses its mother be ore theage o two it is unlikely to survive. Some calvesgo on suckling to three, our or older.

Calves stay very close to their mother orabout the rst six months o their lives and

then begin to move urther away, to exploreand play with other calves. Young calves playenthusiastically! They chase around rollingover each other, having pretend ghts andgenerally rough and tumbling with each other.

As they get older they do this less.

mother AnD cAlf

The bond between a mother and her cal isstrong. For the rst ew months o its li e themother watches her cal very closely andis very protective. She helps it whenevernecessary, but she will also give it a slap withher trunk i she needs to discipline it. As a cal gets older its mother pays it less attention, butelephant calves remain dependent on adults

or several years. In times o danger, the adultsin a herd will orm a ring around the young,

acing out to protect them. All the mothers

share the caring responsibility or an older cal with its mother. These surrogate mothers areyoung emale elephants who are usually thecal ’s aunts or older sisters. They orm strongbonds with the cal and will look a ter it whilethe mother eeds. In caring or the calves, thenon mothers learn the mothering skills they willeventually need.

the mAtrIArch

A emale cal is likely to stay with the herd orthe rest o its li e. Male calves stay with the herduntil they are old enough to mate and thenthey leave. At rst, the males orm small herdso their own called bachelor herds, but eventuallythey become solitary. Although males grow tobe bigger than emales, a emale becomes theleader o the herd: the matriarch.

the polar bear

polAr BeAr fActs…

• or most o their lives, Polar bears are solitary,coming together only or the breeding

season• emales have their rst cubs at around

5 years old

• males are around 6 years old whenthey breed

• Polar bears breed every two to our years

• the emale gives birth to 1-4 cubs,usually 2

• Polar bears are born with their eyes closed

• they weigh around 1.3 lb (0.6 kg) at birthand are around 12 in long (30 cm)

• by the time they leave the maternity denthey weigh around 22-23 lb (10- 15 kg)

• emales and their cubs usually stay togetheror 2.5 years

• Polar bears grow to be the largest landpredator in the world; males can grow upto around 8 t (around 2.6 m) and can weighup to 1,800 lbs (around 800 kg)

• adult Polar bears can live to be 30 years

• a Polar bear spends most o its li e doingnothing but sleeping or lying still

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mAtInG

Adult Polar bears mate between late Marchand early May. This is the only time when bearscome together in the entire year. A breedingpair will stay together or 1-2 weeks be ore

parting.the mAternAl Den

A pregnant Polar bear digs her maternityden in the snow around September orOctober. She chooses a site high up on snowyslopes to give her cubs protection rom malePolar bears. The much bigger male ndsit di cult to climb through the snow. Whilethe temperature outside may drop as low

as -58°F (-50°C), the den will stay at around32°F (0°C).

Polar bears begin li e inside the den. The cubs,usually two, are born between November andFebruary. They grow rapidly eeding on theirmother’s rich breast milk and remain in the denuntil spring. During all that time the motherdoesn’t eat, drink, or de ecate.

oUt on to the snoW

By the time the cubs leave the den with theirmother, as they are seen doing in ,they are strong enough to withstand the

reezing temperatures outside. Their mother

encourages them to take their rst steps onthe snowy landscape they will need to masterby delaying eeding them until they are outsidethe den. Hunger is a power ul motivator.

The cubs stay in the care o their mother or2-3 years. The ather plays no part in rearingthem. By the time they are about three monthsold, they are starting to take solid ood but theywill not be ully weaned rom their mother untilthey are 2-3 years old.

the cUrIoUs BeAr

During the time they spend with their motherthe cubs’ main task is to grow and to learn.Polar bears are curious animals. They watchtheir mother as she hunts or seals on the seaice. They don’t hunt themselves, she providesall the ood or them, but they are learninghunting techniques rom her. Cubs won’t leavetheir mother until they can end or themselves.Even with all the mother’s care, only 50% o the cubs survive their rst year. More will belost in that dangerous period when they rstleave their mother to make their way alone.

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the humpback Whale

hUmpBAcK WhAle fActs…

• Humpback whales breed when they arearound 4-6 years old

• gestation takes 11-12 months• at birth they are 10-15 eet (4-5 meters)

long and weigh up to 1 metric ton

• a emale usually gives birth to 1 cal every1-3 years

• calves drink 160 gallons (around 600 liters)o milk a day

• calves are weaned around 5 months

• calves stay with their mothers or at least2 years

• Humpback whales grow to be about 52 eet(16 m) long, weighing 25-40 metric tons

• Humpbacks can live to around 45-50 years

the sInGInG WhAle

Humpback whales breed in the warm tropicalwaters just north and south o the Equator.It’s here that the male whales sing their longand complex, eerily beauti ul songs. Why orhow Humpbacks sing is still unknown. Bothmales and emales do it, though only malessing the lengthy intricate songs. It seemspossible it is related to communication andin the case o the songs sung in the breedingseason, connected in some way with mating.

During the breeding season Humpbacksdemonstrate courting behaviors like rubbingand stroking each other and slapping thewater with their ns. Once they have mated,it is le t to the emales to raise the young.

mother loVe

A Humpback cal is born near the sur aceand instinctively swims towards reshair to take its rst breath. Like all whales,Humpbacks breathe air. They breathe throughtwo blowholes on the top o their heads andneed to “spout” at the sur ace several timesa minute or more a ter they’ve sur aced roma deep dive. A Humpback mother will useher fippers to help her cal to the sur ace, butwithin thirty minutes o being born, the cal will be able to swim.

The cal suckles on its mother in tropicalseas or our to ve months. During this timeit grows rapidly. Its mother’s milk is high inenergy. For these months the mother cannot

eed at all. The waters don’t contain enoughood. She survives on her blubber.

Once the cal is strong enough, it will join itsmother on the yearly migration o thousandso miles to the polar waters in order to eed.

The mother and cal stay together or up to2 years. During that time the young whale willlearn rom its mother where the best eedinggrounds are and the migration routes it will usein the uture.




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the maNdariN duck

mAnDArIn DUcK fActs…

• the Mandarin duck breeds in easternSiberia, China, and Japan and winters

in southern China and Japan• there are some sedentary pairs residing

in the United Kingdom

• Mandarins do not pair or li e; males ndnew mates every breeding season

• a Mandarin clutch ranges rom 9-12 eggslaid at daily intervals

• incubation lasts 28-29 days

• chicks fy when about 40-45 days old

Mandarin ducks breed in woodland areasnear lakes, marshes or ponds. They alwaysbuild their nests in a hole in a tree up to thirty

eet rom the ground. The emale lines thenest with down.

hIGh DIVInG DUcKs

In the Mandarin chicks are seenleaving the nest in spectacular style! Whenall the eggs are hatched, the mother calls tothem rom the ground. Each chick crawls out

o the hole and launches itsel into a ree all. Astonishingly, all the chicks land unhurt andhead or the nearest eeding ground.

A Mandarin duck’s diet is made up o waterplants, rice and grains. Once they can fy thechicks will leave to join a new fock.




the bird of paradiseof papua NeW guiNea

BIrD of pArADIse fActs …

• there are around 40 di erent Bird o Paradisespecies in Papua New Guinea, each with adi erent display

• males o some species take up to 5 yearsto mature and acquire their spectacularplumage: eathers ru s, elongated andelaborate sets o eathers, head plumes andbreast plates, etc.

• emales breed in their second year

• a ter mating a emale builds a nest and raises

the 1, 2 or perhaps 3 young alone• it is thought that Birds o Paradise are

relatively long-lived birds, with some speciesliving or more than 12 years

pUttInG on A shoW

Courtship or Birds o Paradise has beenelevated to an art orm: a piece o theatre.Fruit is relatively abundant in the Papua NewGuinean rain orest that is their habitat. As aresult, the birds don’t need to spend a lot o time searching or ood and emales don’tneed males to help them eed or protect theiryoung. This has le t the males with time tospend on the business o courtship, whichhas evolved into gaudy visual and auditorydisplays worthy o the most spectacularmusical on stage or screen!

Some males display alone and some ingroups. has a ront-row seat orthe display o the male Six Plumed Bird o Paradise. Technical developments in lminghave made it possible to see the details o thisdisplay, which takes place in the low light o the

orest foor. Every showman needs a stage,and the Six Plumed is no exception. He rstbuilds his dance foor, clearing a small patcho orest foor o leaves and twigs, and pruningthe surrounding branches o leaves. Hedoesn’t want anyone to have a restricted view!He needs all visiting emales to get a goodlook at his per ormance. I any undesirable lea lands on his stage he will jump to remove it justin case it deters a choosy passing emale!

The Superb Bird o Paradise, also seen in, takes a di erent approach. He relies

on sound to advertise his show be ore he evenbegins. Once he has a emale’s attention heuses a combination o sound and his newlyrevealed iridescent plumage to woo her:with, or without, success!

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life cycles: actiVities

GrADes K-2: All KInDs of BABIes

Learning objectives:

• to understand that humans are animals

• to understand that animals grow andchange as they get older

eatures charming and ascinatingsequences o animals caring or their youngand can provide younger children with anexciting springboard rom which to beginthinking about animal reproduction andgrowth.

Tasks

1. How many di erent animals can childrenremember seeing with their babies in the

lm? Who can remember the most? Canthey make a list o them? What do theyremember about what they saw themdoing? Draw pictures o scenes rom the

lm and write captions describing what ishappening.

2. Using this list o animals in , begincollecting pictures or a scrapbook o theanimals and their babies. Compare theadult with the baby animal. How are theydi erent? How are they the same?

3. Choose one o the animals eatured in thelm and nd out more about it to add to the

scrapbook. What is it like when it’s born?Can it see? How big is it? Can it walk?

4. Write a story about a baby animal that losesits mother. How does it nd her again?

5. Many children will already have knowledgeo animal reproduction and rearing thatthey have acquired perhaps rom workinganimals i they live in an agricultural context,

rom pets, or rom observation o wildli ein their immediate environment. They caninclude in ormation on “Animals I Know” intheir scrapbook.

6. The baby animals in all resemblethe adults physically, but this is not true o all babies. Can children think o any babyanimals that do not look at all like the adultanimal? (tadpoles and rogs, caterpillarsand butterfies)

7. Can the children compare themselves andtheir brothers and sisters with the animalsthey see in ? In what ways are humanbabies like the animal babies and in whatways are they di erent?




GrADes 3-6: GroWInG Up


• to understand that animals produceo spring that grow rom young animals to

adults and then reproduce themselves• to understand that in every li e cycle there are

distinct processes and stages

The animals in shown with theiryoung are mainly mammals and birds. The

lm provides a good opportunity or olderchildren to explore the nature o mammalianreproduction and contrast this with birdreproduction.

Tasks

1 . Focus on one o the mammals in andexplore how the baby changes as it grows.

Then, write the mammal’s li e story rombirth to the time when it reproduces itsel .

Tell the story in pictures with each stage o the growing animal’s li e shown in a di erent

rame and captioned. Turn the drawings

into a picture book.

2 . Focus on the sequences eaturing themammals (Polar bear, caribou, elephant,whale). What do the cubs and calves havein common and what is di erent about them(e.g., they are born ‘live’, they suckle their

mothers, they stay with their mothers orextended periods, they are warm-blooded,but they are very di erent in size when born,their mobility is very di erent etc.)? Create achart o similarities and di erences.

3 . Focus on one o the mammals andcompare the baby with a human baby.Create a timeline or the rst ve years ineach o their lives. How are they similar and

how are they di erent? Make a list o thesimilarities and di erences.

4 . Use the Mandarin duck sequence as theocus or studying a bird li e cycle. How is it

di erent rom that o a mammal?

5 . How do the mothers in the lm care or theiryoung? What needs do the o spring havethat their mother must ul ll? The lm showshow well a mother animal cares or her

o spring. Why do children think this drive ina mother animal is so strong? What wouldhappen i it was not? This will introduce theidea o survival o a species.

6 . Design a new Bird o Paradise. How willit display? Create the bird using brightlycolored art materials.

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GrADes 7-12: enDAnGereD


• to investigate how a species becomesendangered

• to explore the role o internationalcooperation in the protection o endangeredspecies

For a species to survive it must reproduce. These species provide an ideal ocus or adiscussion o how a species’ population canbegin to all, become endangered and canrecover. These stories demonstrate howhuman actions can both threaten and save

another species. A GIAnt UnDer threAt:the AfrIcAn elephAnt

For thousands o years elephants have beenexploited or their ivory tusks. Humans havebeen hunting elephants ever since the twocame into contact, but it became widespreadin the 19th and 20th centuries with the use o guns. In just one country, Kenya, the elephantpopulation ell rom 167,000 in 1973 to19,000 in 1989. Although hunting hasdecreased since the ivory ban came intoe ect in 1990, it still continues.

Hunting undamentally changes the structureo elephant populations. The adult males andthe matriarchs o a herd are most requently

the target o hunters because o their largetusks. This has le t so ew males in someareas that emale elephants may be unable to

nd a mate in order to breed. The death o amatriarch impacts the herd as a whole since

she is the holder o so much knowledge. Sheneeds to pass that on to younger members o the amily unit she leads i it is going to surviveand members are going to reproduce.

Loss and ragmentation o their habitat is alsoputting elephant populations at risk as humansettlement takes over land that was oncethe elephants’ range bringing elephants andhumans into direct confict. Where elephantsdo damage to agriculture, water supplies oreven people, they may be killed.

on the VerGe of eXtInctIon:the AmUr leopArD

The territory o the Amur leopard is in north–east Siberia near North Korea. A census o the

Amur leopard in February and March 2007showed that less than 40 o these animalsremain in the wild. The census recorded ourleopard litters, which means that the existingpopulation can still restore itsel . However,

or the long-term survival o the species apopulation o one hundred animals is needed.

A series o actors are quoted as beingresponsible or this catastrophic decline innumbers: the encroachment into the leopard’sterritory o human settlement, the building o




roads, poaching o the leopard or its beauti ulpelt, the intensive exploitation o oreststhrough logging and the impact o climatechange. The Russian World Wildli e Fund iscalling or the establishment o a protectedarea with national park status to protect the

leopard. The di culty is that large predatorsneed large tracts o land on which to live. Anadult leopard home range can be up to 200sq miles (around 500 sq km) and typicallyincludes orested land and deer. Deer, alongwith hares and badgers, are now ound inlower numbers on the Amur leopard’s rangereducing the availability o its prey.

In early 2007 the Russian government decideda ter years o discussion and campaigning bywildli e groups that it would not permit an oilpipeline to be driven through the territory o the Amur leopard saying that the impact o thepipeline would have too damaging an impacton the Amur Bay and its wildli e populations.

BAcK from the BrInK:the AmUr tIGer

In the 20th century the Amur tiger nearlydied out. By the 1940s just 40 remained.But according to recent data rom the WorldWildli e Fund, the tiger population in theSihote-Alinn mountains on the Russia-Chinaborder is now up to somewhere around 500.

The tiger has made its recovery ollowing a co-operative e ort between Russia and China.

The Soviet Union, as it then was, introduced

a ban on poaching tigers in the 1950s and theChinese government supported a global banon tiger products.

However, tiger’s hides can still commandgood prices in the black markets o northeast

China. There ore, poaching continues to bea source o income or impoverished localpopulations. The Russian World Wildli e Fundrecently warned that the species continues tobe critically endangered and would be at riski China succeeded in li ting the global ban ontiger products.

Tasks

1.Compare the plight o the A rican elephantand the Amur leopard. What actors havethreatened the survival o these animals?

Are the actors a ecting the elephantand the leopard the same or are theredi erences? Taking each o the actorsin turn, discuss which are easier or moredi cult to deal with.

2. Discuss the case o the Amur tiger. How didthe actions taken internationally restore thetiger population?

3. What strategies do students think could beused to bring about an increase in the Amurleopard or A rican elephant populations?Students can investigate conservationprojects mounted in the past and presentto sa eguard and renew the population o other endangered species to see i theycould be applied to these animals. Which

might be appropriate and which would bediscounted?

4. Having investigated strategies, studentscan write their own 10-point plan to securethe uture o the Amur leopard and/or the

A rican elephant.

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Documents

BV Earth Ed Guide Online Chapter 5[1]