The Pebble and the Penguin

The Edinburgh Zoo is recently providing and laying out pebbles to help its male Gentoo penguins (Pygoscelis papua) find a mate. The keepers place large doughnut-shaped nesting rings in the enclosures during the mating season for the Gentoo penguins to build their nests in, and then pebbles are gathered and placed within the ring as a blanket for the eggs to be laid on. Pebbles are useful materials for nest-building especially in areas without plants; such nests could possibly save an egg or a chick from drowning if there is a flood.

The male penguin basically sifts through the available pebbles to find the smoothest (slightly flat) one — these pebbles tend to sit the best in the nesting rings — to present to its intended mate, and if the female penguin accepts the pebble and puts it on the nest she’s sitting on, a marriage would be formed — she has accepted the male penguin. Zookeeper Roslyn Talbot mentions that this courtship process also provides an opportunity for the penguin couple to bond. And ‘pebble envy’ could even occur, where the male penguin actually steals pebbles from other penguins, but naturally not without some defensive behaviour from the pebble owners.

Pebbles in Gentoo penguin enclosure at the Edinburgh Zoo

Gentoo penguin with pebble

Gentoo penguin with pebble

This courtship/mating ritual is not only evident in the Gentoo penguins, but also in the Adelie penguins (Pygoscelis adeliae) of Antarctica. In fact, this rather cute courtship behaviour inspired the production of an animated musical film The Pebble and the Penguin back in 1995!

I guess this gives new meaning to “picking someone up”!

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References:

Gentoo Penguin nesting,” by M. Pettitt. Flickr, 10 Jul 2006. URL: http://www.flickr.com/photos/mdpettitt/186727159/

LT Ronald J. Koss, 1963. Report of dental officer for Antarctic support activities for operation deep freeze ’62. Rubicon Foundation, 415: 1-41.

“Pebbles help penguins mate,” by BBC News. BBC News, 31 Mar 2010. URL: http://news.bbc.co.uk/2/hi/science/nature/8597520.stm (accessed on 3 Apr 2010).

Stone, L.M, 2002. Penguins. Google Books, URL: http://books.google.com.sg/books?id=qws0gwkvc4gC&dq=gentoo+penguins+and+pebble+and+mating&lr=&source=gbs_navlinks_s (accessed on 7 Apr 2010).

“The Pebble and the Penguin family fun edition DVD,” by FunkMonk. Wikipedia, 11 Dec 2008. URL: http://upload.wikimedia.org/wikipedia/en/8/80/PEBBLE.JPG (accessed on 6 Apr 2010).

“The way to a Penguin’s heart… a pebble?,” by P. Dickinson. Zoo News Digest, 31 Mar 2010. URL: http://zoonewsdigest.blogspot.com/2010/03/way-to-penguins-hearta-pebble.html (accessed on 6 Apr 2010).

It’s a car! It’s a chainsaw! Wait… IT’S A BIRD!

Imagine you’re walking through the forest and you suddenly hear the sound of a chainsaw nearby; the thought of a tree falling on you is enough to make you scramble for your life. But if you’re in an Australian forest, hold your thoughts and calm down for a bit; you will be pleased to know that the sound of the chainsaw might just be coming from a bird instead – the Superb Lyrebird.

Superb Lyrebird

Superb Lyrebird

Scientifically known as the Menura novaehollandiae, the Superb Lyrebird (above) is a songbird whose specialty is to mimic any sounds that it hears. This is one of the two species of Lyrebirds which exist, with the other being the Albert’s Lyrebird. In a YouTube video from BBC Wildlife, a male Superb Lyrebird can be heard performing amazing mimicries of a Kookaburra, car alarm, chainsaw and camera shutter sounds – mimicries so convincing that you would think they’re the real deal. (Check the video out here!) This vocal mimicry is usually prominent during male displays where male Superb Lyrebirds stand on a “platform” to perform a courtship song which includes its own song as well as imitations of other species and surrounding environment to attract females. While doing so, the male Superb Lyrebird will spread out its tail (above), showing off a stunning display of its feathers.

The Superb Lyrebird’s syrinx (vocal chords) is “the most complex of all songbirds” (Birds.com, 2007) and this gives the bird its astonishing ability to reproduce sounds accurately. The accuracy of vocal mimicry in Superb Lyrebirds is also an “indicator of male age” (Zann & Dunstann, 2008). Although vocal mimicry plays a clear role in the selection of mates, not many studies have been done regarding the relationship between the complexity of vocal mimicry and the level of mating success (Kelly et al., 2008).

References

“Amazing! Bird sounds from the lyre bird – David Attenborough – BBC wildlife” by BBC. BBCWorldwide YouTube Channel, 12 February 2007. URL: http://www.youtube.com/watch?v=VjE0Kdfos4Y (accessed on 27 Mar 2010).

Kelly, L. A., Coe, R. L., Madden, J. R., Healy, S. D. 2008. Vocal mimicry in songbirds. Animal Behaviour, 76: 521-528.

“Superb Lyrebird (Menura novaehollandiae) by kookr. Flickr: Kookr’s photostream. URL: http://www.flickr.com/photos/kookr/3866749339 (accessed on 27 Mar 2010)

“The Marvelous Mimicry of the Lyrebird,” by Editor. Birds.com, 10 September 2007. URL: http://www.birds.com/blog/the-marvelous-mimicry-of-the-lyrebird (accessed on 26 Mar 2010).

Zann, R. & Dunstan, E. 2008. Mimetic song in superb lyrebirds: species mimicked and mimetic accuracy in different populations and age classes. Animal Behaviour, 76: 1043-1054.

The Best Way to Impress the Ladies

KUNG FU PANDA

Remember Po, the extremely clumsy yet skillful warrior in the movie Kung Fu Panda? Well, you will be amazed to know that pandas in real life can perform martial arts too – they can do the handstand!

panda doing handstand2

Research has shown that male giant pandas (Ailuropoda Melanoleuca) often perform such acrobatic acts to “impress the ladies” and intimate their rivals (National Geographic, 2010). When a male panda scent-marks an object, the height of the mark actually lets other pandas know their size and status. Thus, the males often go upside down on their front paws with the aim of pushing their urine as high up a tree trunk as possible. This is done in the hope of attracting the females and scaring off rival competition (BBC Science/Nature, 2004).

Known to be solitary mammals that have little visual and vocal contact with one another, the endangered giant pandas thus rely heavily on chemical communication through scent. Besides using scent to coordinate mating, these remarkable creatures also utilise it to mark their territory and establish social relationships.

On top of the aforementioned handstand position, there are three other distinct gymnastic postures which the giant pandas often adopt to deposit their individual unique scent: squat, reverse on vertical surfaces and leg cock (Swaisgood, Lindburg & Zhou, 1998). They will rub an acidic-smelling substance, secreted by glands surrounding the ano-genital area, on tree trunks and stones through these various methods (Wanglang Nature Reserve, 2001). The males scent-mark frequently year-round, though increasing significantly during the mating season, whereas the females’ marking behaviour occurs predominantly during the mating season (Kleiman, 1985).

Now, looks like the battle for women is no longer just based on looks.

Reference List

Images and Video

BBC Wildlife. (2008). “Giant Panda Bear Does Handstand!”. Retrieved 4 April, 2010 from http://www.youtube.com/watch?v=006ip4ndThE

Kjdrill. (2008). “Upside down Zhennie during the rainstorm”. Retrieved 4 April, 2010 from http://www.flickr.com/photos/kjdrill/2291858483/

Lynch, P. (2008). “Kung Fu Panda”. Retrieved 4 April, 2010 from http://www.thevastpictureshow.com/2008/07/kung-fu-panda-45.html

Articles/Journals

BBC Science/Nature. (2004). “Panda handstand makes its mark”. Retrieved 4 April, 2010 from http://news.bbc.co.uk/2/hi/sci/tech/4043105.stm

Kleiman, D. G. (1985). Social and reproductive behaviors of the giant panda (Ailuropoda melanoleuca). Bongo, 10: 45–58.

National Geographic. (2010). “Giant Pandas, Giant Panda Pictures, Giant Panda Facts”. Retrieved 4 April, 2010 from http://animals.nationalgeographic.com/animals/mammals/giant-panda/

Swaisgood, R. R, Lindburg, D. G., & Zhou, X. (1998). Giant pandas discriminate individual differences in conspecific scent. Animal Behaviour, 57: 1045–1053

Wanglang Nature Reserve. (2001). Panda Facts. Retrieved 4 April, 2010 from http://slack.net/~rd/wanglang/panda_facts.htm