LSM1303 Animal Behaviour

Yes its true!

Red Harvester ants seem almost to eclipse the sophistication of Humans with their flawless coordination in keeping their nest in tip top condition. There is no leader in the colony. Not even the Queen! In fact, egg-laying is the queen’s only responsibility. She has nothing to do with running the colony or assigning workers to specific tasks.

Check out this video to observe their coordination.

Ants create a lifeboat in the Amazon jungle – BBC Wildlife – the “embed” is not available..but DO WATCH IT. =)

Much of this can be attributed to the acute sense of “smell” these ants possess. But instead of sniffing the air, ants use their sensitive antennae to detect chemical odors in their surroundings. The pheromones that these antennae pick up hint to these ants what they should be doing. Put simply by a Harvard Researcher, “Different tasks smell different.”

Harvester ants have 3 main roles, 1) Patrollers, 2) Foragers, 3) Nest Maintainance. The patrollers go out early to ensure it is safe for the foragers to go out and find food. Should the patrollers not return to the colony, the foragers would not leave the nest. The return of the patrollers bring about a scent. When a certain forager smell, say, 15 patrollers passing her, she knows then that that is the right time to leave the nest and forage. The interplay of pheromones and frequency of encounter makes for accurate timing.

These ants also know when exactly they should change their roles. Take for example the percentage of foragers to patrollers to maintainence workers is 50% – 25% – 25%. Should a forager ant fail to “smell” a patroller after many encounters, she would automatically switch her role to become a patroller. This quickly and accurately maintains the correct ratio for the colony to survive.

This site makes use of an interactive applet to explain the receptivity of harvester ants to their counterpart’s scent.

http://serendip.brynmawr.edu/complexity/models/antcolonies/page3.html

Through chemical interactions such as those mentioned above, the colony is able to maintain its efficiency flawlessly. And something for the ladies…note that every single worker ant in the colony is a female. Talk about girl power…

References

MARK SHWARTZ, Ants’ body odor, physical contact get worker ants working, study finds, Stanford Report, 2003, http://news.stanford.edu/news/2003/may7/antchat-57.html

Laura Cyckowski and Paul Grobstein, Ant colonies: Social Organization without a Director?, Serendip/SciSoc Group, Summer 2006, http://serendip.brynmawr.edu/complexity/models/antcolonies/page2.html

I loved this movie when I was in primary school (don’t we all???) so I was super excited when I got to watch it recently again. I was curious on how Willy was doing (in real life) so I began wikipedia-ing whales in general.

I would never have imagined what I found out.

WHALES (WILLY INCLUDED) COULD HAVE BEEN THIS WOLF-LOOKING CREATURE ABOUT 50 MILLION YEARS AGO!!!

Can you believe it?!?!?!

I’m sure you guys are all thinking: how is that possible! How could a large, big brained, land-walking animal evolve over the years to a swimming creature, an ocean dweller and live its entire life in water?

Call it an unfinished story.

The extraordinary evolution of whales started 50 million years ago. It was said that in less than 10 million years, the whales’ ancestors completely transformed themselves from four legged terrestrial animals to Today’s ocean dwelling giants. During the transformation, they lost their legs and all their vital organs required to live on land. Instead, they gained gigantic fins and cute little panda eyes (in Willy’s case of course). Pakicetus, was the oldest known early whale and can be said to be the “transitional” animal between the terretrial mammals and earliest true whales. This small furry wolf-like animal can now be found in the lands of Pakistan. Similarities between the two can be found:

• Their need to breathe air from the surface;
• The bones of their fins, which resemble the jointed hands of land mammals; and
• The vertical movement of their spines, characteristic more of a running mammal than of the horizontal movement of fish.

I managed to find a timeline of the evolution to share with everyone. Isn’t it just extraordinary?

Of course, some details still remain fuzzy,such as gaps in the fossil records and investigations and research are still undergoing. However, scientists have made recent discoveries in Pakistan. They have managed to solve many of these mysteries, and it is now possible to see several stages in the transition of the cetaceans from land to sea. The video below shows the detailed explanation of the scientists’ research:

http://channel.nationalgeographic.com/series/morphed/3001/facts#tab-Videos/06300_00

It might be unbelievable.. that Willy’s ancestors used to live on land. But it’s true! As evolutionary biologist Neil Shubin points out, “In one sense, evolution didn’t invent anything new with whales. It was just tinkering with land mammals. It’s using the old to make the new.”

This got me thinking… Since whales used to have legs.

Can Humans…

do the opposite of a whale evolution & live in the sea afterall?

References:

“http://channel.nationalgeographic.com/series/morphed/3001/facts#tab-facts” When Whales Had Legs. National Geographic Channel, April 8 2008.

“http://en.wikipedia.org/wiki/Evolution_of_Cetaceans” Wikipedia: Evolution Of Cetaceans (Last Accessed: 14 April 2009)

“http://www.pbs.org/wgbh/evolution/library/03/4/l_034_05.html” Evolution Library Website: Whale Evolution (Last Accessed: 14 April 2009)

In the midst of my regular time-killing Facebook surfing, I chanced upon this video shared by my friend on his Facebook account.

That’s right. Fainting Goats.

Laughing now, at the sight of these goats? Are you just as amused at how silly they looked, falling down awkwardly on the grass from slight triggers of shock contributed by the people in the video?

These goats had no choice. Yup! It’s not a “feigning” characteristic they possess, but a genetic disorder instead!

Background Information

Fainting Goats, also known as Tennessee Fainting Goats, Wooden Leg Goats, are actually suffering from a genetic disorder called Myotonic Congenita. This is a condition in which the ‘muscle cells experience prolonged contraction when the goat is startled. The transitory stiffness associated with these contractions can cause the goat to fall down^’.  It is caused by a ‘combination of recessive genes’. ‘This is not a true faint, but a muscular phenomenon unrelated to the nervous system. The degree of stiffness varies from goat to goat, with some showing a consistently stiff response and others exhibiting stiffness only rarely’. It is not a seizure – it doesn’t hurt. After relaxing for about 10 to 15 seconds, they are able to jump back up and resume their activities prior to the startle.

This is obviously an unlearnt behaviour, which applies to all sex and generally the younger generation of goats. This fainting behaviour is lost with growth as ‘older goats learn to spread their legs or lean against something when startled, and often they continue to run about in an awkward, stiff-legged shuffle’.

Picture of a poor young goat stiffened up due to an unexpected startle or scare.

The disadvantages in life faced by the Fainting Goats

Have you ever wondered how would it be like for these goats to survive in the wilderness? For me, the future is bleak, especially for the younger goats which are unwillingly inflicted with such behaviour.

Imagine this scenario – a pack of wolves approach grass grazing sheep and these goats in stealth. Just when they decided to pounce and prey on the flock of sheep, the distressed sheep would then be in their “fight and flight” mode, making a clean getaway while the younger goats would “faint” as per the name of their breed. Wolves then turn their attention and wag their tongues towards these fallen goats instead.

HOW UNFAIR FOR THE GOATS! :( :( :(

Lucky for them, due to their docile and friendly character, they have become ideal pets in the region where they were believed to have originated from – Tennessee.

HOWEVER! It was also due to them being ‘less apt to climb fences and escape from pastures than other goats, and their muscular conformation and high reproductive rate were also valued’. Farmers began to appreciate them. They are then reared for their meat, for ‘Myotonia causes them to have excellent meat to bone ratio and very little body fat. These factors contribute to their flavour, which is described as mild and quite pleasant, especially for people who don’t like “goaty” tasting meat’.

Okay maybe not so lucky after all. :(

More protection in the future?

But things MAY change for the Fainting Goats. It is increasingly recognized as an ‘important genetic resource in the United States’, and it is under ‘high conversation priority’. Hopefully with more understanding and appreciation of the Fainting Goats, their survival would not be at stake in the near future.

So, still laughing?

References

“http://www.albc-usa.org/cpl/tenngoat.html” Breed Information: Tennessee Fainting Goats. The American Lifestock Breeds Conservancy. (Last Accessed: 14 April 2009)

“http://www.faintinggoat.com/index.php?option=com_content&view=article&id=2&Itemid=2” Breed Information. International Fainting Goat Association. (Last Accessed: 14 April 2009)

“http://www.slowfoodusa.org/index.php/programs/ark_product_detail/tennessee_fainting_goat/” Ark of Taste: Tennessee Fainting Goat. SlowFood USA. (Last Accessed: 14 April 2009)

“http://en.wikipedia.org/wiki/Fainting_goat“ Wikipedia: Fainting Goat. (Last Accessed: 14 April 2009)

We all know that birds generally get their food through these channels – eat worms, bugs, sunflower seeds and bread crumbs (if fed by humans). Think about more specific ones like crow even. We have seen a video shown during the lecture that shows in Japan, a crow drops the nut onto the road at the pedestrain crossing such that when the nut gets cracked open by a passing car, it can then fly down to eat the seeds from within the hard nutshell, when the pedestrain light shows green.

Now follow these 2 links that shows u 2 different videos about how birds find more ways to get their food.

1.
http://www.break.com/index/bird-learns-how-to-fish.html
The narrator sounds quite… Funny.

2.
http://www.youtube.com/watch?v=8tmh2yUwhIA
Enjoy the dog, bird and badger! But do watch out for the bird at 00:34.

Anyway, in the first video you can see how the bird cleverly uses the bread found on shore, as bait to lure fish to the surface of the water such that it can then ‘fish the fish out of the water’. Compared to other birds that may have the ability to catch fish such as the Pelican with its distinctively useful throat pouch, or like the Kingfisher that can dive and catch fish, this bird forages using tools like bread in this case. I read abit of the comments. Note that other than those commenting on the narrator, one particular comment actually identified the species of bird to be the Green Heron. I searched for pictures and facts of the Green Heron, and based on what I saw, I agree that the bird captured in the video is indeed a Green Heron. The Green Heron has indeed been identified as one of the few ‘tool-using birds’. They use a variety of baits and lures, such as bread crumbs, insects, twigs etc. to hunt for fish. This method of ‘fishing’ has been believed to be equipped with the Green Herons for since at least afew decades ago when man started investigating on animals who use tools to forage.

Using bread as bait. Slyyyy

Then, as I moved on to the second video, I realised that it actually is the same type of bird! The bird captured in the video is also a Green Heron! Alot of people are actually very fascinated by this act of luring fish to the surface of the water and then fishing the fish out. (As was I when I first saw the videos. Very fascinated. Haha.) But I realised that to researchers who studied these animals who use tools to forage, we would seem to be abit over-reacting. However, it really sets us (or at least me) wondering, how did these animals actually discovered this way of hunting? If they had seen other animals doing it, and then they follow, were there any coaching involved? Like the parent teaching the young to do so. Imagine, how do babies learn to walk? Parents have to hold their hands and make them try to walk. And slowly, they get used to the feeling of walking and as their lower limbs grow stronger, they start to walk on their own. But animals like horses try to stand once they are born. Animals like birds, fly once their wings are strong. You don’t see the parent bird trying to guide their young to fly the way humans guide their babies to walk.

3.
http://www.orenhasson.com/EN/bait-fishing.htm
Oh and I found this one more about crows doing the same thing!

Anyway, back to the Green Heron. The foraging skill of using bread crumbs or insects as baits to lure fish to the surface of the water to hunt them, has now been described as a ‘natural’ trait of them. It just amazes me as to how such skills can be instilled into the animals, written in their genes, such that they do not require to learn how to do something but know how to do it. The other case is about brood parasitism. How the cuckoos will lay their eggs, and their young will just know to kick out the eggs of the host nest.

If animals do not need to learn things to have the skill for survival, and the only thing man knows once they are born, is probably just crying, n maybe poo. We probably don’t even know how to stand like alot of mammals do once they are born. And man has to go through so much just to survive, and live. So who is the more intelligent animal? Us, because we can learn? Or them, because they don’t even have to learn?
References:

“http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Green_Heron_dtl.html“, Cornell Lab of Ornitology. Accessed on 12th April 2009.

“http://www.westboroughlandtrust.org/nn/nn38.php“, by ANNIE REID. The Westborough News, 30th September 2005.

“http://animaldiversity.ummz.umich.edu/site/accounts/information/Butorides_virescens.html“, Dewey, T. and J. Butzbaugh. 2001. “Butorides virescens” (On-line), Animal Diversity Web. Accessed on 13th April 2009.

“http://www.orenhasson.com/EN/bait-fishing.htm“, by Oren Hasson. Accessed on 13th April 2009.

Mind control is a word that is not usually associated with the real world. What comes to mind when this word is mentioned are images from horror movies. However, in actual fact, the manipulation of the mind for the benefit of self is not that far fetched after all! There have been recorded instances of animals that appeared to have the ability to control the behaviour of others through parasitism.

Parasitism refers to a type of relationship between two organisms, in which one receives benefit from the other at the expense of the other organism. Some examples of well known parasites are the tapeworms and fleas.

Tapeworm

While some parasites induce pain, spread diseases and cause general deterioration of the host’s health, there are some parasites that do far more than merely affecting the physical being of the host.

wasp eggs deposited on caterpillar

The trematode parasite, Microphallus sp. was found to affect the behaviour of infected snails radically. The snails are the intermediate host for the parasite while birds are the eventual host. It was found that snails that were infected by the parasite were more prone to linger in open areas, where they were more noticeable by its predators. This bizzare behaviour greatly increases the possibility of the snails being spotted and consumed by birds. Once the parasitized snail is consumed by a bird, the parasite is then able to complete its developmental cycle in the bird’s body. Hence, through the modification of the behaviour of the snail, the parasite significantly increased its chances of completing its development (Levri, 1999).

Another example of such mind control actions of parasites include how wasps affect the behaviour of orb weaving spiders. The wasp Hymenoepimecis argyraphaga parasitizes on its host, the orb-weaving spider Plesiometa argyra by laying eggs on the abdomen of the spider. The spider is then able to carry out its normal daily function and appeared unaffected by the infection while the larva of the wasp feeds on the spider through small holes made on the spider’s abdomen. However, on the night before the larva kills off its host, the spider is induced to make a cocoon web that is able to support the cocoon of the larva, instead of its usual orb shaped web. Upon completion of this task, the spider is then killed and becomes food for the growing larva (Eberhard, 2001).

Normal orbweb vs Web spun by parasitized spider

Researchers are currently looking into the mechanism behind such phenomenon and if successful, this could translate into highly effective pest control measures.

References

Eberhard, W.G. (2001). Under the influence: Webs and building behaviour of Plesiometa argyra (Araneae: Tetragnathidae) when parasitized by Hymenoepimecis argyraphaga (Hymenoptera: Ichneumonidae). Journal of Arachnology 29, 354-366.

Levri, E.P. (1999). Parasite-induced change in host behaviour of a freshwater snail: parasitic manipulation or byproduct of infection? Behavioural Ecology 10, 234-241.