LSM1303 Animal Behaviour Student Blog : courtship display

I'm a drag-queen and I win. ;)

LUO CHUN YIN — Fri, 21 Mar 2008 08:04:00 GMT

Ok, so you've heard of marine animals such as the octopus and even cuttlefish being able to change colour, but I bet you didn't know that for a certain species of cuttlefish, this ability of theirs is so developed that their appearance change can fool their mates as well?

Anyone recognise this strange-looking big fella? I thought it looked quite gentle here in this video actually. Haha. Ok anyway, introducing the Australian Giant Cuttlefish! ( Sepia apama).

SO, what is so fascinating about this fella? Get ready to be surprised! ;)

Basically, some of the smaller-sized males of these big creatures can change their appearance so rapidly that they not only fool their competing male counterparts into thinking that they are female during intense mating competition, hence allowing these mimickers to get closer to the females, but the females themselves, for some reason, actually allow these mimickers to fertilise their eggs! Sneaky little biggies aren't they? Haha.

AND that is not all. According to this ScienceDaily article, ( you can read the full article here), “the cuttlefish can switch between a male and female appearance 10-15 times per minute.” It's no wonder that the bigger males and even the females themselves get confused!

Such behaviour is actually known as “sneak-mating”, which can take the forms of both overt sneak-mating as well as stealth sneak-mating. Of course, the cuttlefish employs all available tools in its arsenal, and that includes the well documented sexual mimicry as well. The latter often “leads to increased acceptance of mating with the female, and to immediate fertlisation, as demonstrated by DNA fingerprinting.” Now I know, the mimicries of animals have so many different purposes!

I couldn't exactly find a video of a smaller male switching its appearance so rapidly, but here is one video of a close-up of skin patterning changes, although by the same scientist who conducted the research mentioned above. There is one here on youtube of giant cuttlefish courtship too! You can clearly see the rapid colour and pattern changes in the male cuttlefish for this one. ;)

This post and all the relevant research that I did was actually inspired by a little chameleon I saw while in school yesterday. While the chameleon was,of course, not as flamboyant as the cuttlefish in changing colour, the distinct two half colours of a brownish-orange and green while it froze beside a tree root and stared right back at me made me wonder if it could change colour at will, or was it because of its surroundings that acted as some external stimuli. While I ended up not finding out the answer to that yet, I stumbled across a few magnificent videos of the flamboyant cuttlefish ( metasepia pfefferi) and became fascinated by cuttlefish instead. So I turned my focus to camouflage by the creatures of the deep instead, and voila! I think, the Australian Giant Cuttlefish certainly tops the list for fully maximising this colour changing ability. :)

References

a. Image used from http://achtel.com/Australian%20Giant%20Cuttlefish.jpg

b. It Pays To Be An Imposter. ScienceDaily. Retrieved March 21, 2008, from http://www.sciencedaily.com /releases/2005/01/050124005322.htm

c. Encyclopedia of Life, http://www.eol.org/taxa/16486539?category_id=194#

d. Youtube, Giant Cuttlefish of the Kelloe, http://www.youtube.com/watch?v=o0zFMb160EI

e. Youtube, Giant Cuttlefish Courtship, http://www.youtube.com/watch?v=MxiH3f-JsO4

Dancing on the way to Paradise…

Chan Si Hui — Fri, 21 Mar 2008 03:45:00 GMT

I have always been intrigued by the behaviors of birds, the way they communicate, the way that they can survive in the wilderness despite being so small and seemingly vulnerable, and also, the way that they attract birds of the opposite sex. From the courtship behavior of the Birds of Paradise, there is definitely more to these birds than people’s view of them having “bird brains”.

What I found interesting of the Birds of Paradise was the way that the male birds dance to court other females. When male Birds of Paradise want to attract the attention of other female, they will do the courtship dance. They will plume up their feathers for the dance, to give them a magnificent coat to attract audiences.

However, before they dance, these males have to clear away part of the forest floor to find a display ground. As will be seen from the video, the Bird of Paradise will flick the leaves and twigs away continuously till it is satisfied with the clean and immaculate clearing. In fact, it continued to do so even though there were no more leaves on the ground! This shows that they are very particular about their “stage”. This is to prevent itself from tripping over and falling, so that it’s “courtship dance” will not turn out to be a dance that will turn away its admirers.

Yes, believe your eyes! That is a Bird of Paradise that you are seeing above. Try spotting its head and body, which was what I tried to do when I first saw this. It actually shows a Bird of Paradise pluming up its feathers, probably in the midst of its courtship dance.

“The adult males have plumes, frills, capes, quills, lacy feathers, and skirts, with tails that may look like expandable fans, whips, twisted wires, and more, depending on the species.”

(please click here for the video on the courtship dance of the Bird of Paradise).

Once on the stage, the male bird first hopped around the stage, before it starts to do its dance. Amazingly, it has all sorts of colourful ornaments on it that can help to show off its dance moves, so as to beat its rivals. As it plumes up its black coat, the white layer of feathers on its chest will be fluffed up, giving it a more colourful look. The white disc on its head will also stand out. Furthermore, it will open up its head fan, being in its most beautiful moment. As it struts around, more and more female audiences started to gather. The male Bird of Paradise will finally stop after it chooses one to mate with.

Just like before any performance, the Bird of Paradise will also need practices before it dances in front of its intended audience! As seen in the video, one of the juvenile birds was practicing on the stage that was cleared previously by his “elder”. But sadly, his dance was not able to attract any females. This was until the adult “master” came back, showing him what a good dance should be like. The latter’s elaborate dance moves and poses are up to standard, able to attract a number of coy females to watch. For the male Birds of Paradise, this display of their courtship dance may last up to several hours, often taking up a significant time in their lifestyles.

Indeed, the courtship display of the Bird of Paradise is one that needs to undergo practice and planning before it can take place. Using their beautiful feathers and ornaments, the males will fluff up their feathers and dance around to attract other female birds. In order to outdo their rivals, each male will show off its best dance and beautiful feathers to earn more admirers amongst the females, getting a chance to mate with them. In the view of such immaculate behaviors, who still dares to think of “bird brain” as having a negative connotation?

References:

“Attenborough- Plumed Bird of Paradise”, 9^th Feb 2007, http://youtube.com/watch?v=cEh-zclVo44

“Birds: Birds of Paradise”, Zoological Society of San Diego, 2008, http://www.sandiegozoo.org/animalbytes/t-bird_of_paradise.html

“Bird of Paradise”, National Geographic Society, 2008, http://animals.nationalgeographic.com/animals/birds/bird-of-paradise.html

“Feathers of Seduction”, Jennifer S. Holland, July 2007, http://ngm.nationalgeographic.com/ngm/0707/feature3/index.html

Lyrebird or “Liar” bird?

GOH HUI SHAN AMANDA — Thu, 20 Mar 2008 13:41:00 GMT

Mention a bird so skillful at imitating sounds and the parrot always comes to mind right away. However, the ability to mimic sounds is definitely not exclusive to parrots.

As it turns out, renowned vocal mimics in the bird world include “mockingbirds, starlings, mynahs, marsh warbler, lyrebirds, bowerbirds, scrub-birds and African robin-chats”. Read more...

The Superb Lyrebird flaunts its incredible adeptness towards mimicry, imitating a Kookaburra, a camera shutter, a car alarm, and a chainsaw!

Watch "Lyrebird”, Youtube.

The Superb Lyrebird (Menura superba, or M. novaehollandiae) is an Australian ground-dweller “named for the shape of their tail when spread in courtship display. The name also aptly suggests a musician”. Read more...

So what inspires the Lyrebird to become such a successful impersonator?

As David Attenborough clearly describes, the male Lyrebird “incorporates other sounds he hears in the forest into a complex song in attempt to out-sing rivals in his courtship display”. As if copying the songs of other bird species lacks some kind of star performance, it extends its repertoire to include the reproduction of man-made sounds.

The Lyrebird goes this extra mile so as to win the attention of the female bird, drawing her into his territory to admire not just his elaborate song, but also his attractive plumes.

The level of mimicry mastered by the Lyrebird is a fascinating illustration of the role of learnt behaviours in social communication.

But what mechanism underlies this ability to produce such complex sounds?

“The muscles of the syrinx (sound-producing organ in birds) control the details of song production; birds with more elaborate system of vocal muscles produce more complex songs”.The Life of Birds by David Attenborough. As it turns out, the lyrebird's syrinx is the most complexly-muscled of all songbirds. Read more...

In addition to its impersonations of other species’ songs, it learns and incorporates the new sounds it is exposed to such as the camera shutter and the car alarm. So while the Lyrebird’s instinctive loud bird song is a product of nature, its integration of other interesting sounds into its song are inspired and nurtured by sounds it hears in the forest environment.

And the adaptive significance of this learnt behaviour in Lyrebirds is clear – to increase its attractiveness and, the chances of mating and reproduction. Large song repertoires increase a male's attractiveness to females.

An interesting question to ponder on: How does the female Lyrebird is able to differentiate the male's "performance" from the actual production of these sounds sounds (e.g. camera shutter, car alarm going off). To the regular hiker making his way through the forest, what may sound like a whole range of birds singing and the sounds of foresters working close by may well be just one "liar" bird's deceptive song.

One wonders, what else does this “liar” have up his sleeves?

Of course, we will always remain intrigued at the ability parrots have to imitate human voices.

Michael Schindlinger’s article “Why do parrots have the ability to mimic?”, lends insight into this amazing ability.

“When parrots are kept as pets, they learn their calls from their adoptive human social partners. Part of their appeal as pets is their ability to sing lower notes than smaller birds and so better reproduce human voices. In the wild, though, their calls may go much higher in pitch and much faster in tempo than any human tutor's voice.”

Once again, the role of environment in learnt behaviours demonstrated.

The benefits of birds’ reliance on learning for vocal development are also described in this account. Read more...

“Some benefits of learning may include development of context-specific calls. Imitative vocal learning is also a reliable social display of neural functions—requiring good hearing, memory…” - qualities even females humans seek out in her mate!

References

“Bird Songs”, by Gareth Huw Davies. The Life of Birds by David Attenborough. Retrieved 14 Mar 2008.

“Lyrebird”, Encyclopedia Britannica - the Online Encyclopedia. Retrieved 17 Mar 2008.

“Lyrebird, From Wikipedia, the free encyclopedia”. Retrieved 17 Mar 2008.

“Why do parrots have the ability to mimic?”, by Michael Schindlinger. Scientific American, 5 Dec 2007.