Beavers saving the environment

The beaver Castor canadensis is the largest rodent in North America and constructs dams with the complexity of what a civil engineer studies for his degree. They are second only to humans in their ability to alter their landscapes and also equipped with pragmatic skills to repair and upkeep their homes. Besides having such a talent, they are found to be monogamous and mate during January and February. Furthermore, they communicate with posture and scent marking, and slap their tails to signify danger of predators.

In the wetlands in Canada, the presence of a beaver had a considerable effect on the amount of open water. The ability to manage water is extremely commendable, and they command an overwhelming influence on wetland creation and maintenance such that they can mitigate the effects of a drought. Climate change has recently stormed the world with its threat to wipe out the planet, and there have been efforts to increase its awareness held at the Copenhagen Summit 2009. It was suggested that beaver impoundments have high resistance to disturbance such as flooding, and that the beaver can mitigate the adverse effects of climate change. However, they are not impervious to long-term droughts, which compromises the survival of their colonies.

It just goes to show that the beavers value adds the environment by its aesthetically pleasing sight as well as in climate change. With such a behaviour to constantly build dams for their shelter and prevention against predators, it still has a good cause to it!

References
National Geographic. Beaver. http://animals.nationalgeographic.com/mammals/beaver/

Hinterland Who’s Who. Beaver. http://www.hww.ca/hww2.asp?cid=8&id=82

Glynnis A. Hood, Suzanne E. Bayley. Beaver (Castor canadensis) mitigate the effects of climate on the area of open water in boreal wetlands in western Canada

The “Hissed Off” Blue-Tongued Skink

Blue Tongue!

Blue Tongue!

The Blue-Tongued Skink is a fascinating lizard! By virtue of the fact, like its name suggests, the lizard has a blue tongue! These interesting lizards are a member of the Skink (Scincidae) family, and they carry the genus Tiliqua. There is a whole myriad of different blue-tongues and they each carry slightly different characteristics. One thing in common, of course, is their possession of a blue tongue. Most blue tongues also have an orange belly!

Although indigenous to Australia and Indonesia, these lizards have made their way to different parts of the world whereby they are highly prized as pets. Easily tamed and docile by nature, these blue tongues make good pets for the family, and are generally safe even when handled by children. They have quite a long life span, living till 20-25 years in captivity, and growing to about 40-50cm in length (depending on the species). Blue tongues in captivity are usually fed with vegetables, fruits, cat food, eggs, snails, earthworms.

A kid holding a blue-tongued skink

A kid holding a blue-tongued skink

The blue tongue serves a different purpose, and this is well-illustrated when the skink feels threatened. Because it has no proper defense or offense mechanism, the skink resorts to hissing and displaying its blue tongue when threatened. This sudden gesture, coupled with the hissing sound and the color of its tongue, helps to scare off threats. The skink also flattens its body to make it look larger. After these warning signs, the skink will not hesitate to bite (and it does deliver quite a powerful bite), so do not try to pick the skink up when it shows these signs!

Hissed off!

Hissed off!

Here is a video of a Shingleback blue-tongued skink (T. rugosa rugosa • Gray, 1825) putting up a demonstration!

References:

Blue-Tongued Skinks: Welcome to Blue-Tongued Skinks.net!

URL: www.bluetongueskinks.net (accessed 09 April 2010)

The Australia Blue Tongue Lizards

URL: http://www.outback-australia-travel-secrets.com/blue-tongue-lizard.html (accessed 09 April 2010)

Blue-Tongue Skinks

URL: http://www.anapsid.org/bluetong.html (accessed 09 April 2010)

Chimpanzees – Cooperative or Competitive?

Considering the fact that Chimpanzees, Pan troglodytes, share 99% identical DNA with human beings, it’s no surprise that we might at times find their behaviour strikingly familiar to ours. In an interesting article in New York Times, writer Carl Zimmer suggested that human beings might have inherited the cooperative nature of chimpanzees “perhaps before the human and ape lineages divided”. He cited other series of experiments which produced the same results as what we see in the video – that Chimpanzees not only cooperate when there is a promise of reward, they also help out at simple tasks like picking up a dropped sponge.

Despite such findings on the cooperative nature of chimpanzees, people are still under the general impression that they are violent animals. Indeed, extensive studies have highlighted that their society is one that is characterized by aggression, whereby succession is determined by conflict. Competition is rife as male chimpanzees fight to achieve a dominant status. Violence is also often displayed to other chimpanzee groups.

The question then seems to be what is the “true nature” of chimpanzees? It is important that social factors ought be taken into account, as there is evidence that suggests that chimpanzees’ ability to cooperate is influenced by factors like tolerance constraints. Perhaps the gender of the chimpanzee might also affect the extent of cooperation or conflict. So far, field observations have provided unclear results of the cooperative behavior of wild chimpanzees. It remains to be explored if competition or cooperation is the more usual behavior of these animals. I believe that whether chimpanzees display hostile or helpful behavior depends greatly on the situation they are in and the presence of other animals around. Ultimately, they are just like humans – moodswings and all.

References

“Chimpanzee Problem Solving by Cooperation” by National Geographic Youtube Channel, 7 December 2008. http://www.youtube.com/watch?v=xOrgOW9LnT4 (accessed on 8 April 2010)

“Chimpanzees Live In Small Family Groups, Are Aggressive And Often A Violent Society”, by J. Harrison. Chimpanzee Information: Chimpanzee Behaviour, 18 January 2010. http://chimpanzeeinformation.blogspot.com/search/label/Chimpanzee%20Behaviour (accessed on 8 April 2010)

“Chimps Display a Hallmark of Human Behaviour: Cooperation”, by C. Zimmer. The New York Times, 3 March 2006 http://www.nytimes.com/2006/03/03/science/03chimp.html?_r=3&oref=slogin&pagewanted=print (accessed on 8 April 2010)

M. N. Muller & J. C. Mitani, 2005. Conflict and Cooperation in Wild Chimpanzees. Advances in the Study of Behavior, 35: 275-299

A. P. Melis, B. Hare & M. Tomasello, 2006. Engineering cooperation in chimpanzees: tolerance constraints on cooperation, 75(2): 275-286

Feeding Frenzy of the Herring Gull

One of the features of the herring gull, Larus argentatus, is that it has a red spot below its beak. This spot is crucial for the parents when feeding the gull chicks. Infants will peck on the red spot of their parents, indicating hunger to them. In turn, parents will gorge out food to feed their child. This behaviour has been found even in chicks that were just born, supporting the existence of innate behaviour (ten Cate, 2009; Tinbergen, 1953).

According to Baerends (1988), the red spot is a sign stimulus that is required to elicit such a pecking response from the chicks. This sign stimulus can be exaggerated to elicit a more vigorous response. As the video showed, by adding an additional 2 more stripes to the yellow stick, the chicks pecked more than usual and also at a faster rate. This exaggerated sign stimulus is called a supernormal stimulus.

References

Baerends, G. P. (1988). Ethology. In R. C. Atkinson, R. J. Herrnstein, G. Lindzey, & R. D. Luce (Eds.), Stevens’ handbook of experimental psychology (Vol. 1, pp. 765 – 830). New York: Wiley.

ten Cate, C. (2009). Niko Tinbergen and the red patch on the herring gull’s beak. Animal behaviour, 77(4): 785 – 794.

Tinbergen, N.  (1953). The herring gull’s world: A study of the social behaviour of birds. London: Collins.

“Herring gulls,” by Imagebroker. Nature, 24 March 2009. URL: http://www.nature.com/news/2009/090324/images/herring-gull.jpg (accessed on 8 April 2010)

“More human than human – herring gull chicks,” by Esthetica1. Youtube, 21 September 2009. URL:  http://www.youtube.com/watch?v=Y5azoIGlz3U (accessed on 8 April 8, 2010).

The breeding behavior of Happy feet

The Emperor Penguin (Aptenodytes forsteri) is the tallest and heaviest of all living penguin species and is mainly living Antarctica. The male and female are similar in height and size: 122 cm in height and weighing anywhere from 22 to 45 kg. Their dorsal side and head are black and sharply delineated from the white belly, pale-yellow breast and bright-yellow ear patches. Like all penguins it can’t fly, instead wings stiffened and flattened into flippers for a marine habitat. They live and breed at the beginning of winter, on the fast ice all around the Antarctic continent. The total population is estimated to be about 200,000 breeding pairs. Emperor penguins can mate when they are 4 years old and can live to be 20 years of age.

Emperor_Penguins,_Weddell_Sea,_Antarctica (Source: Telegraph)

The penguins start courtship in March or April, when the temperature can be as low as −40 °C. A lone male will stand still and place its head on its chest before inhaling and giving a courtship call for 1–2 seconds. After that, it will move around the colony and repeat the call.   Before copulation, the birds bows deeply to each other. Emperor Penguins are serially monogamous. They have only one mate each year, and stay faithful to that mate.

emperor_penguin_kiss_postcard-p239858035829953463qibm_400

(Image source:http://www.zazzle.com)

Breeding pairs of emperor penguins face a problem as they don’t have breeding territories. Therefore, they defend their partnership by staying together during this period.This defense extends to their vocalizing — they remain silent until the egg is laid, so that an unpaired penguin can’t disrupt them.

Yet to keep warm and conserve energy during mating season, emperors must huddle with hundreds of other birds. Huddles form for a few hours, break up for a while and re-form again with different birds, over and over during the Antarctic winter. It’s the penguin equivalent of a mosh pit.

So how does a silent pair of emperors avoid becoming separated amid all the confusion? The answer, according toa study in The Proceedings of the Royal Society B: Biological Sciences, is that they stick close by each other in the crowd.

CHINA

(Image source: http://www2.macleans.ca)

After the female lays its egg, it transfers to the male who will incubate it, alone, for several months.The female will return to care for the chick once it hatches; at that time  the male will go to the open sea to feed. The male will return in a few weeks and both male and female will tend to the chick by keeping it warm and feeding it food from their stomachs.

After 7 weeks of care, the chicks form groups called “crèches” and huddle together for protection and warmth. They are still fed by the parents. The chicks know their parents by the sound of their call. The chicks are fully grown in 6 months, which is the beginning of the summer season in the Antarctic. At this time all the penguins will return to the open sea.

Emperor-Penguins_1212011c

(Image source: Telegraph)

REFERENCES:

Breeding Penguin Couples Stay Close in a Crowd.

http://www.nytimes.com/2009/03/17/science/17obhuddle.html

Emperor penguins behavior

http://www.emperorpenguins.net/behavior.html

Antarctic Penguins

http://www.gdargaud.net/Antarctica/Penguins.html

Emperor penguin mates: keeping together in the crowd

http://rspb.royalsocietypublishing.org/content/early/2009/03/06/rspb.2009.0140.abstract

Emperor penguins

http://www.polarcruises.com/antarctica/articles/wildlife_4/emperor-penguins_4.htm