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01:00An Indian florican, he's got a problem.
01:16He wants to attract females and mate, but in tall grass, it's not easy to tell them where he is.
01:21It's not easy to tell them where he is.
01:51There are, of course, other ways of broadcasting such messages in places where it's difficult to be seen.
02:13A nightingale in an English woodland in spring.
02:26He's recently arrived from his winter quarters in Africa.
02:29He continues singing into the night.
02:55Perhaps because the females who arrive after him usually travel under cover of darkness and may be passing overhead.
03:02Whales sing, too.
03:11The song of the female right whale travels great distances through the water and can be heard by other whales at least five miles away.
03:29Her calls also announce that she's ready to mate, and the males who've gathered around her push and butt one another to get alongside her.
03:40The act of coupling lasts only a few seconds, so the males have to be ready to seize the chance.
03:55Teasingly, she rolls over, preventing the jostling males from mating with her just yet.
04:00She is encouraging competition between her suitors.
04:15The males, who are bigger and stronger, will push rivals out of the way to lie beside her and mate when she allows it.
04:22That way, she achieves the objective of her courtship to secure the best father for her calf.
04:28On the open grasslands of Central Asia, the steppes, lives an animal that issues invitations to prospective partners with a perfume.
04:53The dwarf Siberian hamster.
04:56This little female is about to give birth, but before she does, there is something else she must do.
05:03She marks the vegetation around her burrow with a secretion from beneath her tail.
05:13As the day begins to dawn, she retires below ground to her nest chamber and there gives birth.
05:21Her half-dozen babies are still very underdeveloped, naked and blind,
05:25for they've only spent 28 days growing in her womb.
05:28But she's unlikely to live for much longer than a year, and she has no time to waste.
05:33Now, she must supply her babies with some milk.
05:40But because her life is so brief, and this may be her only breeding season, she's also in a great hurry to mate again.
05:46Her hormones don't allow her to do both things at the same time.
05:50And she has just three hours between delivering the last of her babies and supplying them with milk.
05:57So the effectiveness of that message of perfume that she posted up last night is now crucial.
06:03The wind has spread it all over the steps.
06:06And males within half a mile in any direction will have detected it.
06:13Here they come, full of excitement.
06:15Here we go, full of excitement.
06:27So, once again, she couples.
06:53But hamster mating is quite a long business.
06:56One copulation is not enough.
06:58The male follows her down into her burrow
07:00just to make sure that none of his rivals,
07:03hanging around outside, manages to displace him.
07:09An hour or so later, he's still with her.
07:16The other males have missed their chance.
07:18While all this has been going on during the night,
07:31other hamsters have been wandering around through the grass,
07:34seemingly unaffected by all this excitement.
07:36But why should this little male,
07:43within two or three feet of that female's perfume message,
07:46ignore it when that same message will bring another male
07:49from almost half a mile away?
07:51Well, the fact is that this little male,
07:54although he looks very like the female,
07:56is a different species.
07:58He feeds mainly on insects,
08:00she on seeds and grass.
08:02And her message contained two statements.
08:05Not only, hurry, I want to mate,
08:07but also, this is who I am.
08:09And this little male knew that she was not for him.
08:13And that second part of the message is very important,
08:18because it prevents animals from trying to achieve matings
08:21that can never be successful.
08:22The more crowded the environment,
08:26the plainer these statements must be.
08:29The coral reef has the densest and most varied population of fish
08:32of any part of the sea.
08:37Butterfly and angelfish are among the commonest.
08:40There are many closely related species,
08:43all with very similar shaped bodies, roughly rectangular.
08:46But the color patterns on these rectangles
08:48are as varied as the designs on national flags.
08:52with such clear declarations of identity
09:10emblazoned on their bodies,
09:12no one is likely to court an unsuitable partner.
09:19When courtship begins,
09:20then, of course, individuals must make sure
09:23that their identity badges are prominently displayed.
09:29Boobies are ocean-going birds
09:31that are common throughout the tropics,
09:33and there are half a dozen species of them.
09:36Since several kinds may nest on the same island,
09:39there could be some confusion.
09:40But this is a blue-footed boobie,
09:47and when a male starts to court a female,
09:50he leaves her in no doubt about that.
09:52Blue-foots don't make a proper nest, just a scrape.
10:03But a relic of this nest-making urge remains in their courtship.
10:07And how better to indicate your willingness to mate
10:22than with a little token nest material
10:24deposited on your partner's attractive blue feet.
10:27The blue-foot's identity badge is a permanent one.
10:52Its feet are blue throughout the year.
10:54But other birds only wear their badges
10:56during the breeding season.
10:58Male ducks, this is a wood duck,
11:00grow new feathers each spring.
11:03During the winter, they, like their females,
11:05were a plain brown.
11:07A male magansa,
11:08his female is also drab.
11:10The female ducks incubate the eggs by themselves,
11:20and the sitting duck needs camouflage.
11:23The males reinforce their specific costumes with displays.
11:27The smule bobs his head,
11:29and his female responds invitingly
11:31by vibrating her tail and swimming low in the water.
11:34The golden-eye favours a rather more restrained head bob.
11:44But that is all his female needs
11:45to be convinced that he's the right partner for her.
11:55But how does a duck know
11:56what its appropriate mate should look like?
12:00Females know innately,
12:01but the males have to learn.
12:03The first moving thing
12:05ducklings normally see
12:06as they emerge from the shell
12:07is their mother.
12:09This image becomes imprinted
12:11in the brain of the ducklings,
12:12and for the next few weeks,
12:14they will follow it unwaveringly.
12:19The male duckling
12:20never forgets the appearance of his mother.
12:23And when a little mallard becomes adult
12:25and starts looking for a mate,
12:26it's her that he seeks to match.
12:29But this male duckling
12:30is not a mallard.
12:31He's a young golden-eye.
12:36He hatched from an abandoned egg
12:38that was given to a mallard foster mother.
12:40Though he looks different from the mallard ducklings,
12:43he's completely accepted into her family,
12:45and he follows her wherever she goes.
12:47Next year, if he survives,
12:56he will be in the same predicament
12:58as this adult golden-eye.
13:00He, too, was brought up by a mallard foster mother.
13:04The female golden-eye, impressed by his plumage,
13:07makes all the right signals of acceptance.
13:09Another joins her.
13:14He ignores them both.
13:16They're not what he's seeking.
13:17His displays are directed to a female like his foster mother,
13:21a female mallard,
13:22and she, alas,
13:23finds his signals totally incomprehensible.
13:26But being the right species
13:32is not necessarily enough.
13:34An individual male
13:35may have to have some extra attraction to offer.
13:39This tree stump,
13:40here in the forests of Central America,
13:43contains a pool of water,
13:44and that's just what a female damselfly needs,
13:47because she can only lay her eggs in water.
13:50So any male that can claim this
13:53and drive off rivals
13:54really has something to offer.
14:00This is the biggest of all damselflies,
14:03and the distinctive flight
14:04with which the male proclaims his ownership of a pool
14:07has given it the name of helicopter damselfly.
14:14Rival males are chased away,
14:27but a female will be attracted by his display
14:29and lay eggs in his pond.
14:31He remains on guard after she's gone
14:34and will readily welcome other females,
14:36so that eventually his precious pond,
14:39if it's large enough,
14:40may contain several larvae.
14:42But he is father of them all.
14:51Other male insects
14:52offer other enticements to their females.
14:55Hanging flies in North America.
14:58They are hunters.
15:01Flies are their favorite food,
15:03if they can get them.
15:05But beetles may have to do.
15:07This male has caught a fly,
15:12but he doesn't eat it all.
15:14He uses it as a bait for a female.
15:17To advertise it,
15:18he fans his wings
15:19and disperses a perfume
15:20released from the tip of his abdomen.
15:24A female approaches.
15:26Had this been a small fly or a beetle,
15:36she wouldn't have stayed.
15:37But she approves of this large, juicy one,
15:40and as she feasts on it,
15:42she allows the male to mate.
15:43But he won't let go of his gift.
15:53Transferring sperm from a hanging fly
15:55is a lengthy business,
15:57and it may take him 20 minutes to complete it.
16:01He grips her securely
16:03while she continues to feed.
16:06Mating completed,
16:07he releases her.
16:08She wants to take the remains of the fly with her,
16:11but he wants to keep it,
16:13and a wrestling match starts.
16:20He wins.
16:21Even a second-hand meal
16:23may attract another female.
16:32And within a minute or so,
16:34another female is interested.
16:35Aerobatic skills
16:41are what impress tropic birds.
16:43Both male and female
16:44will have to catch food at sea
16:46for their nesting,
16:47and when adults select partners,
16:49both sexes assess each other's merits
16:51as a likely future parent.
17:00At the beginning of the season,
17:02large groups display together.
17:05the birds pair off,
17:08and then,
17:09for minutes on end,
17:10again and again,
17:12they perform
17:12the most elegant
17:13pas de deux.
17:14A marsh harrier,
17:31seeking to impress his mate,
17:33provides absolute proof
17:34of his prowess as a hunter.
17:37She takes his catch
17:38from him in mid-air.
17:39He gives an exhibition
17:48of slow-speed flying
17:50with legs lowered
17:51over a likely nest site.
17:53The female alone
18:08will construct the nest,
18:10but he will collect
18:11a great deal
18:11of the building material,
18:13and he demonstrates
18:14his ability to do so.
18:15The pair also display
18:27by clasping as they fly
18:29not only building material
18:30on prey,
18:31but one another.
18:32He will continue
18:40to feed her
18:41in this way
18:42throughout the nesting period.
18:43termites,
18:58the favourite food
18:59of the red-backed salamander.
19:01This male has a territory
19:11that contains
19:12lots of termites,
19:13and his droppings
19:14provide the evidence.
19:16They are smooth and even,
19:17compared with these
19:19deposited by a salamander
19:21who's been feeding on ants.
19:24Ants are not nice to eat.
19:27They have indigestible,
19:28horny coverings
19:29to their bodies
19:29and stings loaded
19:31with formic acid.
19:32Not nice at all.
19:33But if that's all there is
19:35in your territory,
19:36well, they're better
19:36than nothing.
19:47A female looking for a mate.
19:50She wants a male
19:51with a territory
19:52rich in termites
19:53where her young
19:53can get a good start in life.
19:57This place is clearly no good.
19:59This, on the other hand,
20:06might be better.
20:17She makes quite sure.
20:23Having convinced herself
20:24of the quality
20:25of this male's territory,
20:26she traces him
20:27to his burrow.
20:39Here she will mate
20:40and leave her eggs.
20:45Moose, in the rutting season,
20:47also develop a fixation
20:49on excrement.
20:51A bull moose
20:51establishes a territory
20:53in areas favoured
20:54by females.
21:09Other males
21:10have to be kept away.
21:11The male has a special way
21:25of encouraging females
21:26to mate with him.
21:28Every day,
21:29he urinates
21:30in special pits.
21:31His urine has a smell
21:41that the females find
21:42both pleasurable
21:42and exciting
21:43and that brings them
21:45into sexual receptivity.
21:46They wallow in the pits,
22:13drenching themselves
22:14in his perfume.
22:17All of the females
22:19in the group
22:19want to turn
22:20but the one
22:21in occupation
22:21is frequently
22:22very possessive.
22:27Perfume is also used
22:28by this bat
22:29to attract
22:30and keep a harem.
22:32He is a sack-winged bat
22:34in Trinidad
22:34and he establishes
22:36a roost for his females
22:37on the side
22:38of a silk cotton tree.
22:39When a female
22:42returns at dawn,
22:43he stretches out
22:44his wing
22:44to expose
22:45a perfume gland
22:46on his elbow.
22:49The females
22:50find this smell
22:51highly attractive.
22:53He wafts
22:55his scent
22:55towards them
22:56and then
23:00hovers in front
23:01of a female
23:02so that his perfume
23:03surrounds her,
23:05a perfume
23:05that stimulates her
23:06and binds her
23:07to him socially.
23:19These bright flashes
23:20and calls
23:21are made by
23:22another bat.
23:23A male
23:31epauletted bat.
23:33The females
23:34of this species
23:35assess these invitations
23:36with care.
23:38Their relationship
23:38with the male
23:39will be no more
23:40than a quick visit
23:41of a few seconds
23:42during which they mate.
23:43But which male
23:44is it to be?
23:46The males
23:47have no extra
23:48inducements on offer
23:49such as rich territories,
23:51nest-making skills
23:52or even bribes
23:53of food.
23:54Only their qualities
23:55as a father
23:56for the female's baby.
24:01Somehow,
24:02the female
24:02must select
24:03the healthiest
24:03and most attractive male
24:05so that her baby
24:06has a good chance
24:06of inheriting
24:07such qualities.
24:09Choosing which he
24:09is to be
24:10demands a close
24:11inspection
24:12of the candidates.
24:12The male
24:19supports the entreaties
24:20proclaimed by his
24:21bristling epaulettes
24:22with energetic honks.
24:25But serenades
24:26can be more
24:26beguiling
24:27than his.
24:28The male
24:53bird of Australia
24:54produces one
24:55of the most varied
24:56and glorious
24:57of all animal songs.
25:07Each male
25:08maintains several
25:09courts in his territory
25:10in the bush
25:10on which he sings
25:12and dances.
25:13He tours
25:14from one to the other
25:14and cleans them
25:15meticulously
25:16before he starts
25:17his performance.
25:18He's a superb
25:44mimic
25:44and an experienced
25:46male can sing
25:47the songs of nearly
25:48all the other birds
25:49in his territory.
25:57That's a very
25:58accurate imitation
25:59of the laugh
26:00of the kookaburra.
26:01The males, like the male
26:21epauletted bats,
26:22take on no parental duties.
26:24They leave nest
26:25building, incubation
26:26and feeding the young
26:27entirely to the female.
26:28So they're able
26:30to devote
26:30all their time
26:31and energy
26:31to these displays.
26:39Females travel
26:40from one territory
26:41to another
26:42assessing the rival males
26:44for the complexity
26:45of their song
26:45and the splendor
26:46of their plumes.
26:47And a particularly
26:48successful male
26:49may mate
26:50with many females.
26:51The liar bird is unusual
27:00in having both
27:01an elaborate song
27:02and magnificent plumes.
27:04Most birds invest
27:05in one or the other
27:06and those that rely
27:08primarily on visual displays
27:09have developed
27:10the most ravishing costumes.
27:14The tragopan
27:15from western China.
27:17He only reveals
27:18the full beauty
27:19of the wattles
27:19on his throat
27:20when a female approaches.
27:49what happens
27:50do say
27:52what happens
27:53to another
27:53Rippee
27:54national
27:55weather
27:55and
27:56prosecutors
27:58in their Medicare
27:59from extreme
27:59and insikin
27:59over the
28:14...
28:15The Palawan peacock pheasant from the Philippines.
28:45The standard winged bird of paradise from the Malacca Islands with some of the oddest of all plumes.
29:15The rifle bird of Australia.
29:45It's this appetite of females for increasingly dramatic spectacles that has forced the males to dance to their tune in ever more extreme ways.
30:09And surely the most spectacular of all is the display of the peacock.
30:15Elaborate plumes, of course, are something of a handicap.
30:37They make it more difficult for the bird to fly, and they also make it more conspicuous for any predator to find.
30:44So it's not surprising that most birds at the end of the breeding season shed them.
30:49But that is a considerable waste, and one family of birds, the bowerbirds, have found a very ingenious way of avoiding these two disadvantages.
30:59This is not a nest. It's a display case built by the male bowerbird in order to show off the objects that he collects to impress the female.
31:09He gathers together flowers, feathers from other birds, anything, as long as it's brightly colored.
31:16The satin bowerbird that built this particular bower prefers blue objects, and he's fussy not only about their color, but their arrangement.
31:24So that if I take this blue parrot feather and put it just there, he won't like it at all.
31:31OK.
31:32Let's say it.
31:36It's so cute.
31:40I can't tell the other birds.
31:47The male alone is responsible for building these showcases.
32:08Females regularly tour the bowers, assessing their riches.
32:12The arrival of one stimulates the male to posture and strut.
32:18But she's not yet made up her mind.
32:21There may be a more impressive bower elsewhere.
32:24A rival and more dominant male appears.
32:34He steals the treasures while the proprietor of the bower is away.
32:39He does more.
32:58He's not only a thief, but a vandal.
33:02And he uses the remains of the demolished bower to reinforce his own.
33:21He now has the most spectacular collection of decorations in the whole neighborhood.
33:37And this individual embellishes his treasury in yet another way.
33:47He paints its walls with a blue paste made from mashed berries.
33:51It's all done to impress the female.
33:54If she's going to mate, it will be here between the walls of the bower that she will receive him.
34:12There are 18 different species of bower bird, each with its own architectural design for a bower and its own aesthetic taste in ornaments.
34:39This is the bower of the golden bower bird.
34:42And up here in the forest, which are rather wetter, there's a kind of fungus which grows on twigs binding them together.
34:49So this bower is a much more solid structure and much less easily destroyed than that of the satin.
34:57Indeed, this particular bower may be as much as 40 or 50 years old.
35:01This is the perch on which the bird displays.
35:04And here are its treasures, which are not blue like the satins, but pale green with white flowers with black seeds in them.
35:11And there's one further difference with the satin bird.
35:14The golden bower bird is a much, much shyer creature.
35:18So if I'm going to be lucky enough to see it, I'm going to have to retreat some distance.
35:32He's got another of those white flowers.
35:47A female having a critical look.
36:15The male sneaks onto a neighboring bower while the owner is away.
36:19The tower of twigs may be a fixture, but the treasures can be filched.
36:24The rivalry between black grouse is rather more obvious.
36:40The males, here displaying in Scotland, have their dancing courts alongside one another on the open moors.
36:46And such closeness inevitably leads to quarrels.
37:11Such an arrangement, however, allows the females to make their assessments and comparisons much more easily.
37:17Those projectingман bees won't be seen like the museum.
37:22They're in his own , so he has the same way that the amount support behind the surgeries.
37:27Howíssimes can be cour望ous, so he feels a bit of size OT.
37:31The年 angus can be the same way that they don't overlook the state of the town.
37:36Their decision seems to be based not only on the splendour of the male's displays and the vigour of their dances, but also where they dance.
38:01The females prefer to mate on the court in the centre of the whole gathering, and the male who's battled for and won that will get the majority of females.
38:23You might think that such mass displays would be impossible in such thick undergrowth as this in Trinidad.
38:31But that's exactly what's going on here.
38:34These little black and white birds are mannequins, and each male has industriously cleared for himself a little dancing court.
38:45What's more, they're all so obsessed with dancing that they don't just do so for a few weeks in the year, but for nine whole months.
38:53And what is more, for 90% of daylight hours within those months.
39:00The males keep their courts meticulously clean and tidy.
39:05They perch together amiably enough in the twigs above their courts, but when a female appears, their mood changes.
39:12Now, each does his best to impress her with his dancing skill.
39:21The strange noises are produced by the males snapping their wings together behind their backs and clicking the quills of special flight feathers.
39:35It seems as if they are, at times, flying backwards because they manage to make a mid-air turn just before they land.
39:47Mannequin dances vary greatly from species to species.
39:50The club winged snaps as he jumps and adopts a posture that draws attention to his scarlet cap.
39:57Blue crown mannequins fly in circles around their display perches.
40:15The golden headed favours a backwards shuffle.
40:39And that movement is elaborated further by the wire-tailed, who flicks the female across her chin with long filaments projecting from his tail.
40:54But these long-tailed mannequins are even more extraordinary, for both are males.
41:09The female has just landed on the right.
41:15This is a double act.
41:16The female will only respond if two males perform together.
41:19But why should apparent rivals help each other?
41:28One is Senior.
41:30He is the one who owns the dancing perch.
41:33Only he will mate with the female.
41:35The other is his apprentice, who's learning the form.
41:38And indeed, this dance does take some learning.
41:52Young males start practicing in their second or third year.
41:56They get their adult plumage when they're four, but they still continue to dance with the younger birds, as this one is doing.
42:02Only when he's eight is he likely to be taken on as an apprentice by a male who owns a court.
42:08If and when his senior partner dies, he may inherit the court and take on an apprentice of his own.
42:14But even then, he will only succeed in mating if the females are impressed by the virtuosity of his team performance.
42:21This male antelope, a topi, is also defending a court.
42:37It wasn't until just recently that we realized that any mammals displayed like this.
42:45And that's just what's going on here in the plains of Kenya.
42:51I'm sitting on the edge of just such a display ground.
42:57Immediately behind me are the two best courts.
43:01Each is held by a male who's trotting around, inspecting the half dozen or so females, who also have horns, who've come to visit him today.
43:10He sniffs one to discover whether she's ready to mate.
43:14Within a few yards of these central courts stands a less successful male.
43:23He has a court, but it's not the best and no females have joined him.
43:27The courts are so closely packed that rivals frequently come face to face on the frontier between them.
43:35As long as they don't cross the line, their disputes are no more than symbolic.
43:42As the day warms up, more and more females thread their way through the courts to the central ones held by the most successful males.
44:07This young calf is accompanied by its mother.
44:13She's ready to breed again, but not with this male, who's a low-ranking one.
44:18He nonetheless tries his luck.
44:24In doing so, he crosses the frontier of his court and immediately his neighbour gallops across to repel the invasion.
44:31The successful males in the center courts have now acquired almost more females than they can manage.
44:49There are so many that squabbles are breaking out between them.
45:01The most successful bulls hold courts around the edges of the display ground.
45:16It's now hot and they're very tired, but they won't leave.
45:32Only by competing do they stand a chance of eventually graduating to a premier position.
45:37But these marginal courts, being close to tall grass, are dangerous places.
45:46A hyena.
45:49A hyena.
45:59A hyena.
46:35Not all get away.
47:05For Atopi, the cost of courtship can indeed be high.
47:20The rewards for all these displays, persuasions and entreaties, however, can certainly be
47:29great.
47:31Yet even coupling may not be the ultimate achievement it might seem to be.
47:36An animal may have to do even more than this if it's to ensure that its genes will pass
47:41on to the next generation and so transcend its mortality.
47:46It will be the final trial.
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