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Archive for the ‘Spring 2014’ Category


The Elephant in the News: An Evaluation and Comparison between Two Articles

June 6th, 2014 by svn2

 

Media is always entertaining or informing us with new things. However, I have learned over time that media sometimes tends to sensationalize stories. Recently, I read an unbelievable report on how elephants can comfort each other. Wary about media sensationalization, I searched for the original research article.  After reading both the news report and research article, I evaluated each one and compared them with each other.

In the original research article, researchers Joshua Plotnik and Frans de Waal (2014) studied Asian elephants’ tendency to console distressed members of their group. Consolation is usually defined as “affiliative physical contact from an uninvolved bystander directed toward a recipient of aggression” (Plotnik and de Waal, 2014). It is demonstrated in only a few species since most animals are not thought to have the cognitive capability for consolation. The researchers believed that elephants are capable of reassurance due to being social creatures with strong bonds to their families. In their research, Plotnik and de Waal studied 26 elephants at Elephant Nature Park in Thailand for several months. They collected data in two groups: post-distress and matched-control. In the post-distress condition, the researchers identified a distressed individual based on certain behaviors (e.g. erecting the tail, extending the ear, and roaring) in response to negative stimuli (e.g. aggression, group separation, and environmental threats). They observed nearby bystanders for 10 minutes. They compared these observations with those of the matched-control condition, in which the same elephants were observed at a different time with similar conditions but no distress stimuli. The researchers found that bystanders were quicker to interact with the upset individual in the post-distress condition compared to the matched-control. These bystanders tended to associate with the individual by touching the individual on the mouth and genitals with their trunks. Furthermore, they vocally responded to the individual with unique sounds, which were not made in the control condition. The researchers also discovered that bystanders would touch other bystanders, and surround their young, a behavior called “bunching.” These results suggest that elephants may have a more developed cognition than some animals since consolation is regulated by complex cognitive mechanisms. Because chimpanzees have similar reassurance behaviors and social relationships, the researchers suggested that convergent evolution may have occurred between elephants and chimpanzees in terms of cognition, a possibility to explore with more research.

An Asian elephant comforting another elephant. Photo by E. Gilchrist.

An Asian elephant comforting another elephant. Photo by E. Gilchrist (Think Elephants International, Inc. CC BY SA).

I have always been interested in human and animal behavior, so I enjoyed reading the research, and learning about the psychology of elephants, creatures that I never recognized were highly intelligent. (more…)

Rice’s Pet Squirrels

June 4th, 2014 by nyn1

 

The gray squirrel, Sciurus carolinensis, is a creature that is very well known across Rice University for being a little too friendly with Rice students. The squirrels here seem to have habituated themselves to a certain lifestyle here that has reduced their levels of alertness and actually changed the way that the squirrels here on campus forage for food.

Rice Squirrel with a Waffle. Courtesy of ricesquirrels.tumblr.com

Upon watching the gray squirrels, I realized that the squirrels here at Rice are the same species of the squirrels that I have observed living around my home, which happens to be a mere 30 minutes from Rice, however, they have striking differences. The squirrels that I noticed here at Rice were very bold. (more…)

Whooper Swan Signaling Behavior

May 30th, 2014 by vld3

 

Originally, the wikipedia page for Whooper Swans focused on their feeding habits and distribution, but focused very little on the behavior of these swans. I added this information about Whooper Swan behavior to the page: http://en.wikipedia.org/wiki/Whooper_Swan#Distribution_and_behaviour.

When Whooper Swans prepare to go on a flight as a flock, they use a variety of signaling movements to communicate with each other. These movements include head bobs, head shakes, and wing flaps and influence whether the flock will take flight and if so, which individual will take the lead. Whooper Swans that signaled with these movements in large groups were found to be able to convince their flock to follow them 61% of the time.  In comparison, swans that did not signal were only able to create a following 35% of the time.  In most cases, the Whooper Swan in the flock that makes the most movements (head bobs) is also the swan that initiates the flight of the flock – this initiator swan can be either male or female, but is more likely to be a parent than a cygnet. Additionally, this signaling method may be a way for paired mates to stay together in flight. Observational evidence indicates that a swan whose mate is paying attention to and participates in its partner’s signals will be more likely to follow through with the flight. Thus, if a Whooper Swan begins initiating flight signals, it will be less likely to actually carry through with the flight if its mate is not paying attention and is therefore less likely to join it.

Kiss and Make Up – Reconciliation in Wombats

May 28th, 2014 by rsg4

 

Competition for limited resources has fueled physical conflict in mammals and other animals. While some physical conflicts result in death of a competitor, individuals often return to peaceful living through reconciliation. Reconciliation is defined as “the first exchange of affinitive behavior between opponents after conflict” (de Waal and van Roosmaleen, 1979). Examples of affinitive behavior include sharing resources, feeding each other, and cuddling (Cordoni and Norscia, 2014). Many mammals follow the Valuable Relationship Hypothesis, which states that kin demonstrate reconciliation more often than unrelated individuals, assuming a previously cordial relationship (Cordoni and Norscia, 2014). Reconciliation reduces stress and aggression, and maintains high-value relationships (such as those with kin) in wild chimpanzees and other mammals (Wittig and Boesch, 2005). I reviewed a study by Giada Cordoni and Ivan Norscia of the University of Pisa involving red-necked wallabies (Macropus rufogriseus) and reconciliation. This was the first study conducted to provide evidence of reconciliation in marsupials. (more…)

Communication and Scrounging in Grackles

May 26th, 2014 by ss55

 

The common grackle, or Quiscalus quiscula, may seem little more than a pest. However, I found that these birds made a surprisingly good study for some of the basic principles of animal behavior.

My first observations were on a cold, cloudy afternoon in Rice University’s west parking lot. A small group of birds was perched on the roofs of several cars. Grackles look a bit like small, lanky crows, with longer legs and tail. They are sexually dimorphic, meaning that there are distinct differences between the sexes. Male grackles are an iridescent blue-green-purple with hints of copper—rather oddly like a patch of gasoline in a parking lot. Females, as we can expect in birds, are much blander, with dull brown bodies and dark-capped heads. Because of this difference, I could tell that there was a mix of sexes in the group—three males and three females.

Male grackle, Quiscalus quiscula. Photo credit to safariari on flickr, used under Creative Commons license (CC BY-NC-SA 2.0).

As the birds hopped and shifted on top of the cars, I noticed that they made several distinct sounds. (more…)

Food For Thought

May 21st, 2014 by asa4

 

The Houston Zoo has many beautiful species held in captivity, including Phoenicopterus ruber, commonly referred to as the American flamingo. I observed a flock of thirty flamingos for foraging behavior on Saturday, February 1st, at 11:30 am. Flamingos are well cited as filter feeders, using their bills and tongue movements to pump water containing food through structures in the beak that allow for filtering (Jenkin 1957).  I observed similar feeding behaviors in both juvenile and adult flamingos. The flamingos placed their beaks in the water and created a vibration, which allows the flamingos to sift through the water. Water waves could be seen as the birds peripherally placed their beaks on the water surface. Occasionally, I observed that a bird would put its head under water and move it in a circular formation around a central point.  This behavior has been described previously as “jig movements” (Jenkins 1957). Based on my observations, this flamingo behavior is a method by which to disturb the bed of the pond. Members of the flamingo flock surprisingly demonstrated minimal variation in their feeding styles. However, I noticed that the juvenile grey flamingos spent much less time foraging for food in comparison to the adult flamingos within the thirty minutes of observation. Instead, the juvenile birds spent more time on land observing and standing next to the adult flamingos. This observation is supported by a study concluding that most flamingo species feed in large flocks (Bildstein et al., 1991).

The flamingos I observed were kept in captivity, so the feeding behavior noted may have been different from what would be observed in the wild. (more…)

Texas Minnow Risk vs. Reward Behavior

May 19th, 2014 by vld3

 

Many organisms walk a fine line, balancing their need for food with their need to avoid predation. Minnows in Texas are no exception to this rule. On a cold day (around 50 degrees Fahrenheit) with no precipitation and partial clouds, I observed several minnows on the edge of a local pond (I observed within a foot of the edge of the pond).  The minnows ranged from about two to about four inches long and appeared to be of the same species and of the family Ciprinidae (Nelson, 2000). The pond had algae and debris lining its edge.

While I was watching the minnows, I noticed that they would continually flick around in a very excited manner. Flicking involved very short, fast movements, in which the minnows usually moved less than an inch in a second or less. Usually, this flicking would bring them to the top of the pond, or even closer to the shore. When the minnows moved, they also appeared to be nibbling on the algae in small bites – taking one nibble and then “flicking away”. Additionally, the minnows moved independently, but seemed to stay around the same group of other minnows. Finally, if I moved and a shadow passed over the water, the minnows would dart away. Their darting had them moving quickly, like with flicking, but in longer strokes – when darting the minnows usually moved out of eyesight, but definitely more than a few inches.

While watching the minnows, I developed several hypotheses regarding what evolutionary advantages some of their behaviors may have served. (more…)

Vampire Bat

May 14th, 2014 by amm18

 

The following includes an excerpt which was attached to the Wikipedia page “Vampire Bat” (http://en.wikipedia.org/wiki/Vampire_bat). The first and last sentence in this excerpt come directly from previous Wikipedia information and are used solely as a reference to identify what was added.

…This has been noted by many naturalists as an example of reciprocal altruism in nature.

It was previously thought that food sharing depended equally on relatedness and reciprocation.[i] However, it has recently been discovered that the predictive capacity of reciprocity surpasses that of relatedness.[ii] This finding suggests that vampire bats are capable of preferentially aiding their relatives, but that they may benefit more from forming reciprocal, cooperative relationships with relatives and non-relatives alike.[ii] Furthermore, a recent study demonstrated that donor bats were more likely to approach starving bats and initiate the food sharing. These findings contradict the harassment hypothesis—which claims that individuals share food in order to limit harassment by begging individuals.[ii] All considered, vampire bat research should be interpreted cautiously as much of the evidence is correlational and still requires further testing.[iii] For example, researchers question vampire bats’ ability to identify kin when past association, or interaction, is controlled.[iii] Similarly, scientists question if bats modify investments based on how other bats cooperate.[iii]

Another ability that some vampire bats possess is identifying and monitoring the positions of conspecifics (individuals of the same species) simply by antiphonal calling.[iv] Antiphonal calling is simply a song or verse sung in response.

Vampire bats also engage in social grooming…


[i] Wilkinson, G. S. (1984). “Reciprocal food sharing in the vampire bat”. Nature 308: 181-184. doi: 10.1038/308181a0

[ii] Carter, G. G., & Wilkinson, G. S. (2013). “Food sharing in vampire bats: reciprocal help predicts donations more than relatedness or harassment”. Proc R Soc B 280: 20122573. doi: 10.1098/rspb.2012.2573

[iii] Carter, G., & Wilkinson, G. (2013). “Does food sharing in vampire bats demonstrate reciprocity?”. Communicative and Integrative Biology  6(6): e25783. doi: 10.4161/cib.25783

[iv] Carter, G. G., Fenton, M. B., & Faure, P. A. (2009). “White-winged vampire bats (Diaemus youngi) exchange contact calls”. NRC Research Press 87: 604–608. doi: 10.1139/Z09-051

 

Group Living

May 10th, 2014 by ss55

 

This post is an edit that I wrote to expand on the “Living In Groups” section on Wikipedia’s “Ethology” page. You can visit the page here.

Benefits and costs of group living

One advantage of group living can be decreased predation. If the number of predator attacks stays the same despite increasing prey group size, each prey may have a reduced risk of predator attacks through the dilution effect1. Additionally, a predator that is confused by a mass of individuals can find it more difficult to single out one target. For this reason, the zebra’s stripes offer not only camouflage in a habitat of tall grasses, but also the advantage of blending into a herd of other zebras2. In groups, prey can also actively reduce their predation risk through more effective defense tactics, or through earlier detection of predators through increased vigilance1.

Another advantage of group living can be an increased ability to forage for food. Group members may exchange information about food sources between one another, facilitating the process of resource location1.  Honeybees are a notable example of this, using the waggle dance to communicate the location of flowers to the rest of their hive3. Predators also receive benefits from hunting in groups, through using better strategies and being able to take down larger prey1. (more…)

Water ripples in Tungara frog interactions

May 8th, 2014 by ss55

 

When a scientist publishes their research in a journal, the flow of information of doesn’t stop there—science journalism is an important form of communication that makes this research accessible to the average person. Because academic readers and casual readers are very different audiences, differences are necessary in the way that the same information is presented. By comparing a popular science article to its primary source, we can see how a skillful writer can turn research into news.

In a recent study published in Science (Halfwerk et al., 2014), a research team investigated how animals integrate multiple sensory systems when receiving another animal’s signal. The researchers worked with male Tungara frogs, which produce mating calls while sitting in shallow water. Although it was previously known that frogs would respond to a neighboring male’s call (by calling faster, or falling silent in either preparation to fight or flee), Halfwerk and colleagues discovered that the water ripples produced by calling are an important factor—other males were significantly more likely to respond when ripples accompanied a recorded male frog call. If the ripples indicated that the call was outside the male’s territory (about a 15 cm circle), males increase their rate of calling. If the ripples were inside the territory, males more often fell silent as they prepared to fight or yield to the competitor. (more…)