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01:00An Indian florican. He's got a problem. He wants to attract females and mate, but in tall glass, it's not easy to tell them where he is.
01:22It's not easy to tell them where he is.
01:52There 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. He's recently arrived from his winter quarters in Africa.
02:59He's on the cover of darkness and may be passing over head.
03:08Whales 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.
03:41The 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.
04:16The 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.
04:54The 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.
05:39But because her life is so brief, and this may be her only breeding season,
05:43she's also in a great hurry to mate again.
05:46Her hormones don't allow her to do both things at the same time.
05:51And she has just three hours between delivering the last of her babies and supplying them with milk.
05:58So the effectiveness of that message of perfume that she posted up last night is now crucial.
06:04The wind has spread it all over the steps,
06:07and males within half a mile in any direction will have detected it.
06:14Here they come, full of excitement.
06:16This video interrupted by her healing.
06:19Let's take pause.
06:28We have understood.
06:34So, 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.
07:28While 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.
07:41But why should this little male,
07:43within two or three feet of that female's perfumed message,
07:47ignore it when that same message will bring another male
07:50from 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.
08:24The 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 colour patterns on these rectangles
08:48are as varied as the designs on national flags.
09:07With such clear declarations of identity,
09:10emblazoned on their bodies,
09:12no one is likely to court an unsuitable partner.
09:19When courtship begins,
09:21then, 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,
09:38there could be some confusion.
09:44But this is a blue-footed booby,
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,
10:05but a relic of this nest-making urge remains in their courtship.
10:19And 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 during the breeding season.
10:59Male ducks, this is a wood duck,
11:01grow new feathers each spring.
11:03During the winter, they, like their females,
11:05were a plain brown.
11:07A male magansa, his 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.
11:28The smule bobs his head,
11:29and his female responds invitingly by vibrating her tail
11:33and swimming low in the water.
11:34The golden-eye favours a rather more restrained head bob,
11:44but that is all his female needs
11:46to be convinced that he's the right partner for her.
11:55But how does a duck know
11:57what its appropriate mate should look like?
12:00Females know innately,
12:02but the males have to learn.
12:03The first moving thing ducklings normally see
12:06as they emerge from the shell is their mother.
12:09This image becomes imprinted in the brain of the ducklings,
12:13and for the next few weeks,
12:14they will follow it unwaveringly.
12:19The male duckling never forgets the appearance of his mother,
12:23and when a little mallard becomes adult
12:25and starts looking for a mate,
12:27it's her that he seeks to match.
12:29But this male duckling is not a mallard.
12:32He'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.
13:01He, too, was brought up by a mallard foster mother.
13:05The female golden-eye, impressed by his plumage,
13:08makes all the right signals of acceptance.
13:09Another joins her.
13:14He ignores them both.
13:16They're not what he's seeking.
13:18His displays are directed to a female like his foster mother,
13:21a female mallard,
13:22and she, alas, finds his signals totally incomprehensible.
13:26But being the right species is not necessarily enough.
13:34An individual male may have to have some extra attraction to offer.
13:39This tree stump here in the forests of Central America
13:42contains a pool of water,
13:44and that's just what a female damselfly needs,
13:48because she can only lay her eggs in water.
13:50So any male that can claim this
13:53and drive off rivals
13:55really 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
14:30and lay eggs in his pond.
14:32He 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 offer other enticements to their females,
14:56hanging flies in North America.
14:58They are hunters.
15:01Flies are their favourite food,
15:03if they can get them.
15:05But beetles may have to do.
15:07This male has caught a fly,
15:13but 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
15:21released 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.
15:54Transferring sperm from a hanging fly
15:56is 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.
16:05Mating completed,
16:08he releases her.
16:09She 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.
16:25And within a minute or so,
16:34another female is interested.
16:40Aerobatic 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.
16:55At the beginning of the season,
17:02large groups display together.
17:07Soon the birds pair off,
17:09and then, for minutes on end,
17:11again and again,
17:12they perform the most elegant pas de deux.
17:25A 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.
17:47He gives an exhibition
17:49of slow speed flying
17:50with legs lowered
17:51over a likely nest site.
18:07The female alone
18:09will construct the nest,
18:10but he will collect a great deal
18:12of 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
18:30and prey,
18:31but one another.
18:40He will continue to feed her
18:41in this way
18:42throughout the nesting period.
18:43Termites,
18:58the favourite food
18:59of the red-backed salamander.
19:10This male has a territory
19:11that contains lots of termites,
19:14and his droppings
19:14provide the evidence.
19:16They are smooth and even,
19:18compared with these
19:19deposited by a salamander
19:21who's been feeding on ants.
19:25Ants are not nice to eat.
19:27They have indigestible,
19:28horny coverings to their bodies
19:30and stings loaded
19:31with formic acid.
19:32Not nice at all.
19:34But if that's all there is
19:35in your territory,
19:36well, they're better than nothing.
19:37A female looking for a mate.
19:50She wants a male
19:51with a territory rich 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,
20:27she 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
20:48a fixation on excrement.
20:51A bull moose
20:52establishes a territory
20:53in areas favoured by females.
20:57Other males have 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
21:43and exciting
21:43and that brings them
21:45into sexual receptivity.
21:46They wallow in the pits,
22:13drenching themselves
22:14in his perfume.
22:18All of the females
22:19in the group
22:19want to turn,
22:20but the one in occupation
22:21is frequently
22:22very possessive.
22:27Perfume is also used
22:29by this bat
22:30to attract
22:30and keep a harem.
22:32He is a sack-winged bat
22:34in Trinidad
22:35and 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
22:45to expose
22:45a perfume gland
22:46on his elbow.
22:49The females
22:50find this smell
22:51highly attractive.
22:54He wafts
22:55his scent
22:55towards them
22:56and then
23:01hovers in front
23:01of a female
23:02so that his perfume
23:03surrounds her,
23:05a perfume
23:05that stimulates her
23:07and binds her
23:07to him socially.
23:19These bright flashes
23:21and calls
23:22are made
23:22by another bat.
23:30A male
23:31epauletted bat.
23:33The females
23:34of this species
23:35assess these
23:36invitations
23:37with care.
23:38Their relationship
23:39with the male
23:39will be no more
23:40than a quick visit
23:41of a few seconds
23:42during which they mate.
23:44But which male
23:45is it to be?
23:47The 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.
23:57Somehow the female
24:02must select
24:03the healthiest
24:04and most attractive male
24:05so that her baby
24:06has a good chance
24:07of inheriting
24:07such qualities.
24:09Choosing which he is
24:10to be
24:10demands a close
24:11inspection
24:12of the candidates.
24:19The male
24:19supports the entreaties
24:21proclaimed by his
24:22bristling epaulettes
24:23with energetic honks.
24:25But serenades
24:26can be more
24:27beguiling than his.
24:28The lion
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
25:10territory in the bush
25:11on which he sings
25:12and dances.
25:13He tours
25:14from one to the other
25:15and cleans them
25:16meticulously
25:16before he starts
25:17his performance.
25:27He'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.
25:49That's a very
25:59accurate imitation
26:00of the laugh
26:00of the kookaburra.
26:19The males,
26:20like the male
26:21epauletted bats,
26:22take on
26:23no parental duties.
26:24They leave
26:25nest building,
26:26incubation,
26:26and feeding the young
26:27entirely to the female.
26:29So they're able
26:30to devote
26:30all their time
26:31and energy
26:32to these displays.
26:40Females travel
26:41from one territory
26:42to another
26:42assessing the rival males
26:44for the complexity
26:45of their song
26:46and the splendor
26:46of their plumes.
26:47And a particularly
26:48successful male
26:50may mate
26:50with many females.
26:59The lyrebird
27:00is unusual
27:00in having both
27:01an elaborate song
27:02and magnificent plumes.
27:05Most birds
27:05invest in one
27:06or the other
27:06and those
27:07that rely primarily
27:08on visual displays
27:10have developed
27:11the most ravishing
27:12costumes.
27:14The tragopan
27:15from western China.
27:17He only reveals
27:18the full beauty
27:19of the wattles
27:20on his throat
27:20when a female
27:21approaches.
27:47with someuna
27:48.
27:53.
27:55.
27:55.
27:58.
27:58.
28:10.
28:10.
28:11.
28:11.
28:12.
28:12The Palawan peacock pheasant from the Philippines.
28:42The standard-winged bird of paradise from the Malacca Islands, with some of the oddest
28:52of all plumes.
29:12The rifle bird of Australia.
29:42It's this appetite of females for increasingly dramatic spectacles that has forced the males
30:06to dance to their tune in ever more extreme ways, and surely the most spectacular of all.
30:12Here is the display of the peacock.
30:34Elaborate plumes, of course, are something of a handicap.
30:38They make it more difficult for the bird to fly, and they also make it more conspicuous
30:42for any predator to find.
30:44So it's not surprising that most birds, at the end of the breeding season, shed them.
30:50But that is a considerable waste.
30:52And one family of birds, the bowerbirds, have found a very ingenious way of avoiding these
30:57two disadvantages.
30:59This is not a nest.
31:02It's a display case built by the male bowerbird in order to show off the objects that he collects
31:08to impress the female.
31:10He gathers together flowers, feathers from other birds, anything, as long as it's brightly coloured.
31:17The satin bowerbird that built this particular bower prefers blue objects, and he's fussy not
31:22only about their colour, but their arrangement.
31:25So that if I take this blue parrot feather and put it just there, he won't like it at all.
31:32So that if I take this blue parrot, I can take this blue parrot, I can take this blue parrot.
32:00The male alone is responsible for building these showcases.
32:07Females regularly tour the bowerers, assessing their riches.
32:14The arrival of one stimulates the male to posture and strut.
32:20But she's not yet made up her mind.
32:22There may be a more impressive bower elsewhere.
32:28A rival and more dominant male appears.
32:35He steals the treasures while the proprietor of the bower is away.
32:43He 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.
33:27He now has the most spectacular collection of decorations in the whole neighbourhood.
33:42And this individual embellishes his treasury in yet another way.
33:48He paints its walls with a blue paste made from mashed berries.
33:52It's all done to impress the female.
33:55If she's going to mate, it will be here between the walls of the bower that she will receive him.
34:13There are 18 different species of bower bird, each with its own architectural design for a bower...
34:20...and its own aesthetic taste in ornaments.
34:27This is the bower of the golden bower bird.
34:30And up here in the forest, which are rather wetter, there's a kind of fungus which grows on twigs binding them together.
34:37So this bower is a much more solid structure and much less easily destroyed than that of the satin.
34:44Indeed, this particular bower may be as much as 40 or 50 years old.
34:59This is the perch on which the bird displays.
35:01And here are its treasures which are not blue like the satins, but pale green with white flowers with black seeds in them.
35:07And 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.
35:36A female, having a critical look.
36:06The male sneaks onto a neighbouring bower while the owner is away.
36:20The tower of twigs may be a fixture, but the treasures can be filched.
36:24The rivalry between black grouse is rather more obvious.
36:41The males, here displaying in Scotland, have their dancing courts alongside one another on the open moors.
36:47And such closeness inevitably leads to quarrels.
36:50. . . . . . . . . . . . . . . . . . . . . .
37:12Such an arrangement, however, allows the females to make their assessments and comparisons much more easily.
37:17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
37:47Their decision seems to be based not only on the splendour of the males' displays
37:58and the vigour of their dances, but also where they dance.
38:02The females prefer to mate on the court in the centre of the whole gathering,
38:05and the male who's battled for and won that will get the majority of females.
38:17You might think that such mass displays would be impossible
38:28in such thick undergrowth as this in Trinidad,
38:32but that's exactly what's going on here.
38:35These little black and white birds are mannequins,
38:38and each male has industriously cleared for himself a little dancing court.
38:44Once more, they're all so obsessed with dancing
38:48that they don't just do so for a few weeks in the year, but for nine whole months,
38:54and what is more, for 90% of daylight hours within those months.
39:01The males keep their courts meticulously clean and tidy.
39:06They perch together amiably enough in the twigs above their courts,
39:09but when a female appears, their mood changes.
39:14Now, each does his best to impress her with his dancing skill.
39:28The strange noises are produced by the males
39:31snapping their wings together behind their backs
39:34and clicking the quills of special flight feathers.
39:37It seems as if they are at times flying backwards
39:40because they manage to make a mid-air turn just before they land.
39:48Mannequin dances vary greatly from species to species.
39:52The club winged snaps as he jumps
39:54and adopts a posture that draws attention to his scarlet cap.
39:57Blue-crowned 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,
40:50who flicks the female across her chin
40:52with long filaments projecting from his tail.
40:55But these long-tailed mannequins are even more extraordinary,
41:07for both are males.
41:09The female has just landed on the right.
41:15This is a double act.
41:17The female will only respond if two males perform together.
41:20But why should apparent rivals help each other?
41:29One 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 practising in their second or third year.
41:56They get their adult plumage when they're four,
41:59but they still continue to dance with the younger birds,
42:01as this one is doing.
42:03Only when he's eight is he likely to be taken on
42:06as an apprentice by a male who earns a court.
42:09If and when his senior partner dies,
42:11he may inherit the court and take on an apprentice of his own.
42:15But even then, he will only succeed in mating
42:17if the females are impressed by the virtuosity
42:20of his teen performance.
42:22This male antelope, a topi,
42:35is also defending a court.
42:38It wasn't until just recently
42:40that we realised that any mammals displayed like this.
42:46And that's just what's going on here in the plains of Kenya.
42:50I'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,
43:05inspecting the half-dozen or so females,
43:07who also have horns,
43:08who've come to visit him today.
43:11He sniffs one to discover whether she's ready to mate.
43:14Within a few yards of these central courts
43:21stands a less successful male.
43:24He has a court, but it's not the best,
43:26and no females have joined him.
43:30The courts are so closely packed
43:32that rivals frequently come face-to-face
43:34on the frontier between them.
43:36As long as they don't cross the line,
43:41their disputes are no more than symbolic.
43:42As the day warms up,
44:02more and more females thread their way
44:04through the courts to the central ones
44:06held by the most successful males.
44:08This young calf is accompanied by its mother.
44:14She's ready to breed again,
44:16but not with this male,
44:17who's a low-ranking one.
44:23He nonetheless tries his luck.
44:25In doing so, he crosses the frontier of his court,
44:28and immediately his neighbour gallops across
44:30to repel the invasion.
44:31The successful males in the centre courts
44:47have now acquired almost more females
44:49than they can manage.
44:54There are so many
44:55that squabbles are breaking out between them.
44:57The least successful bulls
45:26hold courts around the edges of the display ground.
45:29It's now hot, and they're very tired.
45:31But they won't leave.
45:33Only by competing do they stand a chance
45:35of eventually graduating to a premier position.
45:40But these marginal courts,
45:42being close to tall grass,
45:44are dangerous places.
45:47A hyena.
45:48A hyena.
45:55A hyena.
45:56A hyena.
46:28Not all get away.
46:58For a topi, the cost of courtship can indeed be high.
47:16The rewards for all these displays, persuasions and entreaties, however, can certainly be great.
47:29Yet 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 on to the next generation and so transcend its mortality.
47:45That will be the final trial.
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