LSM1303 Animal Behaviour Student Blog : courtship

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

Macho "Mums"!

GLADY STEPHANNY — Fri, 21 Mar 2008 07:55:00 GMT

As most of you should have known, male pregnancy is ubiquitous in the fish family of Syngnathidae, which includes species such as pipefishes, seahorse and sea dragons. It is also the only family in the animal kingdom to exhibit such characteristics.

Seahorses have a unique way of courtship and their display of affection is to me, amazing.

Step 1: Let's Dance!

When both seahorses have mutual interest in each other, they court for several days. They may change colours, swim side by side holding each others’ tails and twirl around in unison. They may even cling onto the same sea grass.

Step 2: C'mon baby..

After a few days of courtship, the male pumps water through the egg pouch on his trunk. This would balloon and gape open to display its emptiness. Once the female’s eggs reach maturity, she and her mate abandon grips on any anchors and drift upward out of the sea grass, often spiralling as they rise. After the female squirts her egg, her body slims while the male’s bulges. They both sink to the bottom while the female swims off.

Step 3: Constant Loving Care

The male’s pouch provides oxygen for 21 days by having prolactin, the hormone that governs milk production in women. Throughout his pregnancy, his mate visits him daily for about 6 minutes of interaction. They change colour, hold each others’ tails and wheel around see grass fronds, just as they did during courtship. The female swims away and they continue their daily business until the next day.

Step 4: Only You~

Interestingly, the female refuses to mate with other males during the pregnancy period of her ‘husband’. Such infidelity cannot be tolerated in a monogamous relationship as the seahorses’.

During lecture, we learnt that some species have sex-role reversals as the female grew more aggressive and become physically bigger in size. In the seahorses’ aspect however, the males continue to be the aggressive ones who engage in tail-wrestling. Interestingly, though the male seahorse is the nanny of the child, he remains to be a macho dad. Or should I say mum?

References:

http://www.bio.tamu.edu/USERS/ajones/seahorse.html
http://jhered.oxfordjournals.org/cgi/content/full/92/2/150
http://www.sciencenews.org/articles/20000311/bob9.asp
http://www.spiracanada.com/spiralbound/2004/beltaine/seahorse.jpg

A Bower Bird and his "Bachelor Pad"

SRI ASILAH BTE SUBARI — Thu, 20 Mar 2008 18:39:00 GMT

Human males should certainly learn a few lessons on the art of romance from a male bower bird. That statement may seem absolutely absurd on the apparent sense but perhaps this video might change your mind.

The Vogelkop bower bird (Amblyornis inornata), the world's greatest bower-builder, is a medium-sized, approximately 25cm long bowerbird of the mountains of the Vogelkop Peninsula at Western New Guinea, Indonesia. Despite the males being drab-looking, they have a reputation of being an accomplished masterbuilder with a passion for interior decoration, and are able to construct the most fascinating pieces of architecture in the avian world. A male Vogelkop bower bird may typically dedicate about 9 to 10 months each year building and then adorning his bower with carefully chosen colourful knic-knacks and intricate finds that are scoured through the forest. The bower is solely designed as a "bachelor pad" to seduce and attract females to mate and not for nesting or raising the young.

Each bower has its own decorating scheme and males go to great lengths to ensure that their collections are in perfect condition. Old materials are replaced as required and they try to outshine their neighbours by searching for the rarest and most spectacular materials which are then arranged in an aesthetically-pleasing manner. While waiting for a female to visit and inspect his bower, a male would constantly fine-tune his structure, by experimenting with various designs, colours and decorations, and rearranging them. All these are done in an effort to create the perfect romantic mood.

The video that is highlighted above in particular showcased David Attenborough in a forest in New Guinea, observing a male Vogelkop bower bird's astonishing effort to decorate an elaborate and extraordinary cone-shaped hut-like bower in an attempt to impress the females with his extravagant display of treasures. In this stellar example, the whole treasury which spans about 5 to 6 yards across the area includes a "cleaned" front lawn which is neatly planted with moss, heaps of shiny hardened wings of the black beetle, orange fruit, orange dead leaves, black fruit, acorns from local oak trees, and red flowers. All of these colourful ornaments were brought specially by the dedicated male Vogelkop bower bird and properly arranged in order to show off his exhibition really well.

These avian architects have long captivated scientists from all over the world with their exceptionally bizarre courting behaviour. Many studies have been conducted to understand how such complex traits evolve and function, and how it plays a role in sexual selection. The bower birds, which have been closely-related to the birds of paradise and the lyre birds, have led some researchers to regard them as the most advanced of any species of bird.

So ladies, don't you just wish that men would be as romantic as a Vogelkop bower bird when it comes to matters of seduction? Nevertheless do not despair guys, as perhaps you may start by revamping and renovating your room. Yes there is still hope.

References:

"An Odd Bird" - retrieved from NATURE: Bowerbird Blues website, http://www.pbs.org/wnet/nature/bowerbird/odd.html
"Bowerbirds" - retrieved from http://montereybay.com/creagrus/bowerbirds.html
"Amorous Architecture" - retrieved from Nature: Bowerbird Blues website, http://www.pbs.org/wnet/nature/bowerbird/amorous.html
"Bachelor Pad: Vogelkop Bower Bird - Amblyornis inornatus - Animal Architects". Science World. Sept 13, 2002. Retrieved from http://findarticles.com/p/articles/mi_m1590/is_1_59/ai_95845324/pg_1
"Vogelkop Bowerbird" from Wikipedia, the free encycopedia. Retrieved from http://en.wikipedia.org/wiki/Vogelkop_Bowerbird
"Attenborough - Bower Bird" - video retrieved from http://www.youtube.com/watch?v=GPbWJPsBPdA&feature=related

Fairy Penguins in red light district

TEOH YUE LING ELLEN — Thu, 20 Mar 2008 15:14:00 GMT

Granite Island has been specially designed to make it easier for the penguins to breed. They have ready-made burrows and taken special precaution to make the island penguin-safe. The penguin population is dwindling (ironically due to tourism) and they are trying to revive it. On a recent trip to Granite Island, Australia, we were fortunate enough to watch penguins as they were coming back from a day out at sea with their catch to feed their young. Apart from the usual guidelines of observing wild animals like not to feed, approach or disturb them with loud noises, there was a particularly interesting note of caution which caught my attention: “No flashlight, only RED light can be used.” to shine at the penguins. According to the guide, it is only under red light, that the penguins would behave normally. As a result, the pictures turned out like this:

note that it was pitch dark except for the stark red light obvious to us humans, but not the penguins

Vision

Fairy penguins (Eudyptula minor) breed and live on the island. They are also known as little penguins as they are the smallest known species of penguins. Penguins have a flat cornea that allows for clear vision underwater. They are, as many avian birds, able to see the ultra-violet range of the light spectrum. Since their receptors have higher sensitivity towards colours with shorter wavelength (UV light), sensitivity towards red light(with longer wavelength, at the other end of the spectrum of visible light) would decrease. [link] Hence, penguins would behave naturally under red light as they are unable to detect it. However, colours are in fact only perceived in the brain, penguins may not see additional UV colours and may perceive colours differently from us. In order to fully understand this phenomenon, we have to find out how penguins perceive colours. This would better our comprehension of their signals, and give us an insight to the function and evolution of the various colour vision systems that exist across different species.

[I was thinking, since penguins and birds can see UV light, are they able to detect the female UV jumping spiders]

Communication

A full grown penguin is only about 40cm tall. They live in groups by the coast in burrows.

penguin at the mouth of the burrow

The penguins would venture out to sea in the day in search of small fish and squid for food and return just after dark, using the absence of light as a camouflage from predators. While we were there, we observed that penguins used a mixture of something like a cackling/quacking sound for communication. There are three main types of penguin calls. There’s contact call for maintaining communication among the colony, display call to be used between couples and threat call to warn the colony of intruders. I would suppose that threat call is the easiest to recognise because of the urgency and loudness of the call which makes it effective Click here or here to listen to a sample of penguin sounds.

Penguins’ interesting mating selection behaviour is also noteworthy. The male penguins would walk along the shore in search of the nicest and shiniest pebble to present to a female penguin. They may walk the shore for the whole day and drop the pebble at the feet of the female. If she picks up the pebble, they would become mates for life. Penguins practise monogamy. And for communication between partners, penguins use the display call. As penguins live in large colonies and their tuxedos look pretty much the same, it is each others’ call which they recognise and respond to.

I'll end off with a video of fairy penguins

References:

http://www.indianchild.com/what_do_animals_see.htm, What do animals see. Retrieved 17 March 2008

http://www.bio.bris.ac.uk/research/vision/4d.htm, Ultraviolet Vision, University of Bristol 2007. Retrieved 17 March 2008

http://www.usbyte.com/common/approximate_wavelength.htm, Color Wavelength. Retrieved 17 March 2008

http://www.seaworld.org/animal-info/info-books/penguin/communication.htm, Penguins – Communication, SeaWorld. Retrieved 17 March 2008

http://www.aad.gov.au/default.asp?casid=229, Australian Antarctic Division - Sounds of Antarctica. Australian Government. Retrieved 17 March 2008

http://www.bio.davidson.edu/people/vecase/Behavior/Spring2005/Harshaw/MatSys.html, Mating System. Retrieved 17 March 2008

http://www.canongate.net/Lists/Animals/11ExamplesofUnusualMatingHabits, 11 Examples of Unusual Mating Habits, Canongate. Retrieved 17 March 2008

Romance is in the air: Birds' scent could attract mates

PEREIRA GEMMA LEE — Thu, 20 Mar 2008 14:15:00 GMT

      According to an article in the National Geographic News (2003), recent studies have been drawn towards a neglected area of research concerning the role of smell in the courtship behaviour of birds. Known as allanointing, (Douglas III, 2008) these are signals used by animals to communicate.

     The crested Auklet, a seabird found in Alaska and Siberia, is one such bird that has been studied. According to a particular investigation (Douglas III, 2008), it is said to allanoint when choosing a mate by rubbing the bill, chest, head and neck over the latter’s wick feathers. The scent produced by the crested Auklet has been likened to peeled tangerines (Hagelin, 2007) and described as a pungent, citrus-like odour. According to Douglas III (2008), the stronger the odour transmitted, the more sexually attractive they become.

   An experimental study on the function of this crested Auklet’s feather odour concluded that it played a definite social function (Jones, et al., 2004). In the experiment, male and female models of the crested Auklet were applied with a synthetic chemical scent, while the control models had no added odour. Both females and males responded to the corresponding models of both sexes by approaching the scented models more closely and for a longer period of time. Though neither made sexual displays of courtship behaviour, the study did not exclude this possibility. It noted that odour could have a significant function during the courtship behaviour itself, which was beyond the scope of the study. It is clear however, that smell has a social function among the crested Auklets, and that it could also play an important role in mating.

    Hagelin’s (2007) suggests that a reason why scent might play an important role in the courtship behaviour of crested Auklets is that they nest underground in the dark. This clearly points to the possibility of a heightened importance for scent in the mating of the crested Auklet, instead of the visual and vocal displays that have often been the focus of studies in the courtship behaviour of birds.

    To conclude, research in this area appears to be in its initial stages, but, as mentioned earlier, the role of scent as a social function is undeniable, and opens up possibilities to its importance in courtship behaviour among birds. Interested parties might want to pay attention to another bird in the study of allanointing among birds. This is the Kakapo, an endangered species of parrots found in New Zealand. According to Hagelin (2007), it produces a very strong, sweet scent that smells like dust and honey, and the birds have a very strong sense of smell themselves. It is however, difficult to study because it only mates every three to seven years.

References:

Douglas III, Hector D. 2008. “Prenuptial perfume” Alloanointing in the social rituals of the crested auklet (Aethia
     cristatella) and the transfer of arthropod deterrents.” Naturwissenschaften. 95,1:45-53.

Hagelin, Julie C. 2007. “The bird’s nose knows.” College Campus News. Retrieved March 19,2008.
     (http://www.collegenews.org/x6881.xml)

Jones, Ian L., Julie C. Hagelin, Heather L. Major and L.E.L. Rasmussen. 2004. “An experimental field study of the
     function of crested auklet feather odor.” The Condor 106:71-78.

Pickrell, John. 2003. “Smell may play role in bird courtship, study finds.” National Geographic News. Retrieved
     March 20, 2008.
     (http://news.nationalgeographic.com/news/2003/05/0527_030527_birdscent.html)