Friday, October 30, 2009

I Spy...An Eastern Screech Owl! Dee!!

Living in Massachusetts, chances are that you’ve been woken up numerous times by the ‘fee-bee’ or ‘chick-a-dee’ call of the black-capped chickadee. This small bird frequents this area year-round and has been the study of many experiments concerning its mobbing behavior and its call. Its southern counterpart, the Carolina chickadee, was the study subject for Chad Soard and Gary Ritchison of Eastern Kentucky University. These researchers recently published an article in Animal Behavior describing how the ‘chick-a-dee’ call of the Carolina chickadee changes with the presence of a specific predator.

It was discovered that the Caro
lina chickadee’s alarm calls varied with the size and threat of the predator. Their alarm call is the ‘chick-a-dee’ and varies with the number of ‘chick’ or ‘dee’ notes. They discovered this by using bird skins of various chickadee predators and other birds of prey that don’t usually threat the chickadee. The larger, lower threat predators, like a red tailed hawk, elicited more ‘chick’ notes, while the smaller, higher threat predators, like an eastern screech owl, elicited more ‘dee’ notes. They also tested this correlation with playbacks of songs with more ‘chick’ or ‘dee’ notes. Overall, the researchers saw less mobbing with an increase in ‘chick’ notes and more mobbing with more ‘dee’ notes played. In addition to this strong behavior, predators with a threat level in between the red tailed hawk and the eastern screech owl had a moderate response.

This study is great example of graded communication signaling. The other chickadees in the population can respond as a group to the signal that one individual makes, which overall benefits the population from predation. They also have the ability to relay the signal of how dangerous a predator actually is, which overall conserves energy of the population and allows them to focus more time on other activities, i.e. foraging. The next step for Soard and Ritchison is to test how this pattern is similar in other chickadee species to see other ways that this species can communicate with co specifics.


Soard, C.M., Ritchison, G. 2009 'Chick-a-dee' calls of Carolina chickadees convey information about the degree of threat posed by avian predators. Animal Behavior, article in press.


Posted by Christine Rega (6)

Thursday, October 29, 2009

The Honey Bee "Dance"

The subject of a honey bee "dance language" has long been both intriguing and controversial. It is widely accepted that honey bees use floral cues to decide which flowers are the most worth its energy to forage (the flowers with the most pollen/nectar). However, in addition to the floral cues many scientists now believe there is a dance language involved.

Worker bees who return to the honey comb with pollen or nectar communicate with other foragers by dancing. The dancing portrays to the other workers about the distance and direction of where the worker bee just was. In this way the bees can most effectively direct and recruit each other to collect nectar.

When an experienced forager returns to the honey comb from a flower that deserves another look from another bee the forager will perform a dance. In this dance she will give information about both how far away this flower was and in what direction it was in. There are 3 different types of dances that give information about distance. If the plentiful food source is less than 50 meters away a round dance is performed. A distance of greater than 150 meters warrants a waggle dance. And for a distance in between 50-150 meters a sickle dance is performed (a cross between the round and waggle dances).


The direction of the food is being given during these dances. The bees will give the direction relative to the sun. And depending on how long certain parts of each dance is, the other worker bees can gauge about how far away the source is. For example, the duration of the straight walk in the waggle dance is how the honey bees judge exactly how far (2.5 seconds means approximately 2,625 meters away) (NCCES). The relationship between straight walk duration and distance away is linear.

This particular instance of animal communication is both complex and fascinating and solidifes honey bees as an important species worthy of further study and conservation. Original work on the "honey bee dance language" was done by German Nobel Prize winner Karl von Frisch, a professor of zoology at the University of Munich.

http://www.cals.ncsu.edu/entomology/apiculture/PDF%20files/1.11.pdf

-Jillian O'Keefe (week 5)

Wednesday, October 28, 2009

Baby Bats Imitate Dad's Songs

Actual Article ->> http://sciencenow.sciencemag.org/cgi/content/full/2009/1007/3
(with video)

After learning about birds and how they seem to learn their songs at a young critical phase, I decided to find out more about this phenomenon and came about this article. Young bats are known to imitate the noises or songs of adult males they hear in the nest. What is interesting and adds another twist to this story is that the males that are in the nest aren't necessarily their biological parents. This supports the idea that although their is a species genetic component to their song learning bats can learn the songs of other unrelated bats and not just from their own parents.

I think that this study is very important to animal communication. The bird models we have learned about in class are great but a mammal example adds more to understanding the link between imitation and actual speech comprehension and production.

posted by Alliam Ortiz
Cats and Their Owners: Who Truly Has Control?

Interspecies communication exists in a variety of species, with an entire spectrum of intentions. The bolas spider releases a moth sex pheromone to lure male moths to their death; deer exhibit tail-flagging to alert predators that they, thedeer, are aware of their presence; many species of birds share or understand panic calls or behaviors from other species of bird, warning of imminent danger, etc. A more complex and perhaps unnatural form of interspecies communication occurs when two differing species co-exist in the same habitat. The example in this example, an article by Jennifer Viegas – reporter for Discovery News – is between domesticated pets and their human owners.

A new vocalization has been identified and studied in cats, called “solicitation purring”. This purr is particularly common when trying to rouse owners from sleep in the morning. Ten cats were recorded in the study, and this particular call was identified as urgent by nearly all fifty participants. This study’s lead author, Karen McComb, along with colleagues Anna Taylor, Christian Wilson, and Benjamin Charlton determined different types of cat purrs based on acoustic structural analyses.

McComb explained that what cats seem to be doing for the special purr "is producing the low fundamental frequency and its harmonics by muscular activation" -- what has been associated with typical purring -- "but also voicing a cry, probably with the inner edges of the vocal folds, which is then superimposed on the sound's frequency spectrum.
-Discovery News

While cats purr to each other and during states of solitary relaxation, the solicitation purring is strongly exaggerated and higher pitched when communicating with humans. The anatomical structure of a cat’s larynx is key to producing these calls, which are interpreted by humans as urgent. The animal’s vocal folds allow it to produce sounds – purrs and particularly meows – that can strongly resemble a crying baby. Any cat owners can surely attest to this phenomenon, myself included. This similarity innately draws human attention, as would the cry from a distressed baby.

The researchers are still unsure of whether these are learned behaviors by the cats, as they are found to be the most effective modes of communication with their owners, or if we, as humans, have chosen pets whose acoustic signals we find “recognizable and comprehensible”. Personally, I think it is a combination of the two theories. Mammals are social creatures, and when co-existing with another mammal, it is necessary to establish some form of successful communication.

Posted by Ashley Paon (5)

Tuesday, October 27, 2009

Whales: A journey into my obsession, part 2

Whell Whell Whell, here whe are again, whith more whales! They are sooo great. *To know how to properly read the first sentence, watch this:



On a related note, if that clip entertains you at all, or if you like Andy Samberg (especially if you only know him from "I'm on a boat") I HIGHLY recommend you go find the movie Hot Rod and watch it.




Today's article is about sperm... whales, specifically... not like last time where I was like "eh, we got some humpbacks, some dolphins, some narwhals, some unicorns...". The article is fairly short but extremely enticing, which left me wanting more, like really good french food, which is never filling... ever (the people who ordered this food were smart and doubled up on the drinks to fill the extra space).

Sperm Whales use specific sounds in their individual calls to keep calls from overlapping. They apply specific patterns of "clicks" in their calls, which not only can indentify them individually (as these researchers have found), but also let other whales know when their call will finish. So basically, whales are A) much more polite than humans (esp. girls I meet at parties that are clearly uninterested), in that they actually wait for the other to finish talking, and B) extremely intelligent, because they change the timing of the clicks in an orderly fashion according to how long their call will be.

It's as if Katy Perry warned us before she started singing "I Kissed A Girl", saying "Alright everyone, be prepared for approximately a three minute torturous repetition of the song you've heard over, and over, and over...", except in the whales case, it's probably more like "hey everyone what's up, I'm Bob, I'm trying to find this girl I met at the plankton buffet the other day, anyone seen her?".

The researchers went on to show that, like I mentioned briefly earlier, this has been shown to be the case on an individual-to-individual basis, meaning each whale has it's own specific series of clicks. It is believed that this allows them to recognize each other from afar based on these clicks, similar to our own "cocktail party effect", which is what allows us to hear our friends call our name at crowded gatherings over the hollering and hootenannies before we stumble out after them.

via: article

-Alex C Mojcher, week 5

Note: Kathleen, clearly a fellow whale lover, posted her blog before me while I was still filling mine with hyperlinks. Sorry about the double articles. I'll probably just write another post later this week.

I'm going to take this opportunity to recommend you all visit my casual blog my friends and I maintain. Hopefully Sir Houlihan will not mind this.
READ IT HERE!

Comment Replies:

Bethany- Thanks for enjoying my post, I appreciate the compliment. I'm not sure what software they used to encode the clicks, but they definitely did use something. The article says that something was developed specifically for this project- so maybe they wrote their own audio analysis, data analysis, or statistical analysis software to get the job done. As for the clicks, not all whales use clicks. Blue whales use an extremely loud, low frequency hum that we have to speed up/raise the pitch of just to be audible for humans. Check out the comparison:

Sperm Whale

Blue Whale

Humpback Whale (fast forward this one because the guy talks forever)

Carlos- The clicks are pretty awesome, I agree. Sperm whales have these things that look like lips, of course they aren't actually lips, that are thought to make the noise. From what I can find, the evidence is supported, but no one has factual evidence. Here is what they look like:

Valve
Valve (parted)

The clicks are their primary source of communication and is used for all contexts, according to a paper I found- social gathering, mating calls, migratory communication, etc.

Tricia- Thanks so much for the compliments! I try to have as much fun as possible with this assignment and I'm glad you're enjoying it. I tried to find something... anything... about similar social manners in other animals. I couldn't find anything confirming or denying this in any other animals. I'm sorry! My guess is that species that don't interrupt each other are the minority, but I'll keep my eyes out.

Sarah- Thank you too for the compliments, I'm glad you liked the article. I could find absolutely NOTHING on the evolution of this communication. Whales are some of the most mysterious creatures simply because of how hard they are to study, so we're still just figuring out the basics of their communication. Based on the massive size of these animals, I would guess that it evolved pretty early. They can't travel in large packs because there would never be enough food found for all of them to eat, so they had to spread out and still be able to communicate effectively. Hopefully this satisfies at least a bit of your curiosity.

Deysha- Ha, thank you for the compliment- it quite a useful skill, I must agree. I found a whole bunch of studies about the cocktail party effect and how the phrase was coined, but the only other phrase I could find was used on the quasi-illustrious Wikipedia: the Figure-Ground Phenomenon (though an auditory version of the phenomenon, as the real Figure-Ground has to do most often with visual cues). The "figure" is what the subject pays attention to, i.e. their own name, as far as this topic goes, and the "ground" is the "noise", or I guess in this case the cocktail party. Some dorky psychologist called it the "Party Chat brain filter".

Crystal- Thanks so much for the compliments, I'm glad you like my writing! Ok, so the simple answer to your question about why whales are so polite: because they're the coolest. Whether they want to wait to hear others, or want others to wait to hear them, is like a weird version of the "chicken before the egg- which came first" question. I have no idea if that will ever be studied, or how, but I think it probably evolved just out of necessity. If multiple whales call at the same time, they overlap, both calls are lost and energy is wasted. Maybe they have some sort of hierarchy in the system, where weaker or younger callers wait their turn after stronger/older callers... one of the researchers in a recording on the Cornell database mentions hearing strong versus weak callers, so that's my little educated guess.

Thanks again everyone.

Whales are polite Conversationalists

A link to the article can be found here.


Whales are marine vertebrates that communicate by sending vocal signals through their environment, the ocean. In the ocean, these signals can travel very long distances which is extremely important since the ocean is so large, but it also means that they will encounter thousands of other vocal signals from other whales and marine animals at the same time. This article compares the sounds heard in the ocean by a whale, to how a room full of people at a cocktail party would sound to humans. Much like humans, whales have the ability to tune their hearing to particular signal that they want to listen to. What makes whales hearing so unique is that they can detect rhythms in the ocean chatter that is virtually impossible for the human ear to detect.

Several marine biologists at Littoral Acoustic Demonstration Center developed a tool to detect these rhythms which act as identifying agents for each specific animal. These biologists also found that the whales use a technique in which they change intervals between echolocating clicks. This helps to prevent cluttering the echos from their calls. Marine biologist Natalie Sidorovskaia suggests that whales are "polite listeners" that strive to not interrupt each other.

This communication strategy seems to work well for whales in exploring their environment faster and more efficiently. It also seems to be used to identify whales by variances in the rhythm of their calls and clicks. It is quite amazing to me that these whales are able to keep their calls from overlapping in such a vast environment with so much other clutter being exposed to them at all times. More specific details of the results are scheduled to be presented next week to the Acoustical Society of America. In these results I would be interested to see if there if there was a pattern in the length of time between calls of an individual whale that would make it easier for them to not overlap calls, if they were programed to only call at certain times, or if it is simply a matter of listening and knowing when to respond.

--Kathleen Goller (Group B, Week 5)

Metalhead Monkeys?

Most animals do not tolerate our music or seem to like it in the least bit but a study published by David Teie suggests that monkeys respond to music with “monkey content”. In the study cotton top tamarins listened to songs that were based on their own calls and the music seemed to peak their interests and even alter their moods. Teie pointed out that human music is constructed for human perception and based on human development, therefore it only appeals to humans. To create a monkey song Teie used tamarin calls and manipulated the rising and falling of the pitches and the duration of the sounds. The songs contained two types of messages, fear and friendly affiliation. When the monkeys heard the fear song the monkeys displayed anxious and fearful behaviors. Upon hearing the affiliation song the monkeys calmed down and sometimes even foraged. When played human music the monkeys did not pay attention to it but when played Metallica it seemed to calm the monkeys! Teie also hopes to compose species specific music for the National Zoo so the animals can have a new type of enrichment activity.
-Sara Ku (Group B)
http://dsc.discovery.com/news/2009/09/01/monkey-music.html

In your face poopers



Research has found that wolves are very strategic about where they deposit their scat. Wolves do not do their business in any old place, instead they select plants that maximize the visual impact and odor distribution of their feces.

Isabel Barja inspected wolf scat in a region of the Iberian Peninsula. During the study, 101 wolf scats were identified on plants, with 74.8 percent of them placed on conspicuous substrates, indicating they served a marking function. Computer analysis of these choices revealed that plant selection by wolves was not random, with the animals consistently defecating on plants of a certain diameter, height and species.

Barja said that, "the wolves select positively only poplar-leaved rock rose, Spanish white broom and maritime pine for fecal marking." These are plants that can match wolf heights and also that "stood out against the homogeneous background of more common plants." She also noted that sometimes up to three wolves would defecate on a single, "popular" plant.

The same logic may explain why dogs often do their business at particular places when on walks with their owners. "In an urban setting, a fire hydrant can be a prominent landmark. If a dog relieves itself there, other dogs could smell its presence 30 yards away." She also said that canines appear to emphasize height when marking with urine, with dogs "trying to pee as high as they can on fences and other objects in their environment." Like a person pumping up their chest and muscles to look big and impressive, highly placed urine could suggest the individual may not be one to reckon with. "That's probably why when little dogs urinate, they often lift their back leg up as high as possible, sometimes looking as though they're nearly falling over, because they're trying to pee as high as they possibly can."

Barja worries that clear cutting of vegetation in the wild could disrupt wolf fecal marking, and says "it is important to maintain the vegetation of the human constructed roads in the territories of the wolves."

Posted by Brittany Monteiro (5)

Honeybee Dances Rich in Information



You would be hard pressed to find a Biology student that has never heard about the honeybee waggle dance. The waggle dance is a well-studied and sophisticated example of animal communication, that has been well-studied over the last forty years. Honeybee foragers use the waggle-run portion of their dance to communicate information about direction, distance, and the profitability of a patch of forage. Honeybees also will perform a circle dance, which conveys information that a food source is near enough for other foragers to use an olfactory gradient to find it. A recent study by Abbot and Dukas at McMaster University shows that honeybees also convey information about ‘dangerous’ flowers in their dance.

Abbot and Dukas trained honeybees to visit two equally profitable artificial flowers. The flowers were placed approximately 250 meters from the colony, and about 60 meter apart. One flower was considered safe, while the other flower contained a cue for predation risk. They cued for the predation risk by placing two recently killed bees on the experimental flower, but they were placed so that they would not interfere with other forager bees. Trials were run on warm days, and the amount of foragers near each flowers were equalized before the trial began. Eight trials were run for a duration of thirty minutes each, and observers at the flowers notified hive observers when an individual bee spent more than one full minute at the flower. The hive observers recorded the number of waggle runs performed by the focal bees.

The results of this study were clear. On average, the bees returning from safe flowers performed about 20 times more waggle runs than bees returning from waggle runs. This was consistent with previous findings that honeybees avoid flowers associated with danger, and that experienced foragers will steer naïve foragers away from the ‘dangerous’ flowers. This study shows that honeybee dances convey information about predation risk and patch profitability into their number of waggle runs, and are an even more complex and effective method of communication than we could have guessed.

Abbott, K. R. & Dukas, R. 2009. Honeybees consider flower danger in their waggle dance. Animal Behaviour 78:633-635

Posted by Heather Gore

Thursday, October 22, 2009

Spider Foreplay Can Kill!

Yes, you heard me! A male spider is 1 to 2% the weight of its female counterpart. In order to mate with the female the male must essentially court the female through a series of web vibrations, web spinning, and female abdomen drumming. New research by Jeffrey Stoltz has found that if this courtship does not occur for a period of at least 100 minutes than the male spider will not survive this mating ritual and will instead become dinner. If a male does complete his required "foreplay" than he may climb onto the female and complete the courtship and safely escape. On a side note, others males may try to steal his hard-work and sneak up to the female and mate with her while he continues his wooing. This scenario either ends in an early snack for the female or just plain cutthroat thievery.
Males tend to fight to mate with females and the quickest, tiniest ones are more likely to win, which might account for their small stature. Why are the females so much bigger? One theory that Stoltz gave out was that these females have to be bigger to act as a referee and defend herself against the fighting males that want to mate with her.
One question that has not been solved that Stoltz refers to is the way that females discriminate against potential male suitors. Overall if the tiny males don't want to be dinner they better be able to distract her attention for those 100 first precious minutes!


-Alex Bourdois (4)

Wednesday, October 21, 2009

watching fights raises fish hormone levels

http://draco.unine.ch/webdav/site/ethol/shared/Oliveiraetal2001Nature.pdf


Cichlid fish fight for dominance and territory, the fights are thought to be regulated by androgens, and these interactions play an important role in the communication among cichlid fish. in this study male "observer fish" were laced in isolation for 7 days, in order to regulate hormones then were allowed to watch conspecifics over a course of 3 days. Hormones were taken from urine and showed that andorgens were produced by just watching two other males fight. I thought this was an interesting article because I wanted to look at ways of communication (hormones) and types of animals (fish) that havent' really been disussed too often. Below is a direct quote from the article. ----GINA FORTUNATO

"motivation of indi-
viduals to adjust to changes in their social
environment; androgen production is itself
determined by sexual status and by social
contacts among conspecifics"

Tuesday, October 20, 2009

A Helping Hand Upon Request


In the October 14th, 2009 Science Daily article, “Chimpanzees Help Each Other On request But Not Voluntarily, ” the author reviews an experiment that gives insight into the evolution of altruism. Altruism, or the selfless concern for the well being of others, can be seen in various human behaviors, but is seemingly lacking in almost all other species. Most would agree that such selfless acts would be a waste of energy, and there for would not evolve, since the receiver reaps all the benefits. However, the study discussed in this article has shown that such behaviors may exist in our close relative, the chimpanzee.

Researchers at the Primate Research Institute and the Wildlife Research Center at Kyoto University have found that chimpanzees will help others of their species even in the absence of personal gain. Under the principle investigator, Shinya Yanamoto, behavioral studies were completed using twelve chimps; three unrelated adult pairs, and three mother-offspring pairs. Two types of experiments were done to demonstrate selfless acts among the different pair subjects. The first experiment required the trading of tools between chimpanzees. This was done by setting up separate pens, each with different tool-required enrichments that rewarded food. A window allowed for contact between chimps and the tools needed for the enrichment tasks were swapped before each experiment. The second experiment further tested the ‘helping behavior’ by only putting one tool in the wrong pen. This way there was no benefit from the trade as in experiment one, and the ‘giver’ chimpanzee would not he benefiting in anyway. In both experimental types, and with in all pair types the chimpanzees transferred tools to help their partner.
A major observation made was that in most cases one of the partners would ‘ask’ for help either by putting out their hand, poking the other through the window or clapping. This occurred in both related and unrelated pairs as well as in both experiment types. Since this was the case, researchers concluded that communication plays a large role in encouraging altruistic behaviors. It was proposed that this could possibly be done so that help is only given when needed and energy is not wasted on unnecessary altruism.

In conclusion, this article points out a couple important ideas. First, it may be possible that such a behavior evolved because it was helpful to the species; but it is also possible that chimpanzees gain emotional satisfaction for helping one another as humans do. Another important idea is that emotional behaviors which seem very hard to dissect may have evolved in humans just as all other things have. Lastly, even though the idea of sending a message ( clapping/putting hand out) and benefiting exists in this case, there is also another element of giving and not getting anything back in return which in some ways contradicts basic ideas of communication and behavior.
Posted by Jackie Connolly ( week 4-group A)

Are You My Mommy? Because You Don't Look Like It...

Read the article here.

Some animals are just not made to be parents. This is the case of the Maculina rebeli of the European meadows, a species of butterfly who just cannot be bothered to bring up its offspring. Instead, it gives the responsibility to a species of ants (Myrmica schencki).

The pupae of this butterfly have developed a unique set of tricks that fool the ants into raising them. They emit a scent that mimics the ants' smell and gets the ants to welcome it into the nest. The nurse ants that care for the ant larvae also take care of the pupae of the butterfly just as if it were one of their own. The butterfly pupae even learn how to beg for food like the ant larvae.

But it does not stop there. The pupae even demand special treatment. The queen ants make subtle sounds that let the worker ants know of their high status. The pupae have learned to mimic these sounds as well as the ant smell. This gives them as high of a status as a queen ant. If the nest is disturbed, the pupae are the first to be rescued. If there is a food shortage, the pupae's status ensures it a meal, in the form of murdered ant larvae personally killed by the nurse ants. In an experiment, a pupa was put in the same area as a queen ant (normally they would not encounter each other in the nest) with some worker ants. The worker ants ignored their own queen in favor of the pupa's signal. They attacked and killed their own queen.

The tools that the butterfly pupae possess successfully trick the ants into raising them as their own. They are fed, protected, and treated as queens. In this way, they successfully grow up to be viable adult butterflies.

-Tricia Carlson (week 4)

Monday, October 19, 2009

Chemical Signaling in Males of the Long-Nosed Bat

For bats, olfactory signals are necessary for communication. The variety of scents produced in bats is very diverse, and in most cases males produce a larger and more diverse variety of odors. This mostly occurs during the mating season. These chemical signals also play important roles in attraction, individual recognition, and mate selection. There are a few species of bats that have been found to produce smelly sebaceous secretions in their interscapular region. This is referred to as a sebaceous or dorsal patch, and is prominent only during the mating season.

A study was done to evaluate the differences between body traits of males with and without dorsal patches. Males with a dorsal patch had larger testes , were lighter, and were less parasitized. These changes make males more attractive to females. Males will often smear several body fluids on their dorsal patch. These odors might signal readiness to mate. The combo of chemicals from saliva, urogenital fluids, feces, and glandular secretions provide each individual with a unique odor signature. This way individual males can be identified.

Dorsal patches could signal male quality and readiness for mating. They send a signal to females that a male is higher quality and ready to mate. The dorsal patch may also send a cue to females that the male is sexually mature. Females are more likely to mate with males with a better developed dorsal patch. There are no known disadvantages to having a dorsal patch. However, more testing needs to be done to fully understand the relationship between seasonal reproduction, dorsal patch development, body fluid usage, and mating success.

link to article: http://www.bioone.org.silk.library.umass.edu:2048/doi/full/10.1644/08-MAMM-A-324.1

Posted by: Emily Crete

revised 10/24/09

Chemical Communication Rules for One Frog Species

Anurans are known primarily for their use of auditory communication. Most other forms of communication are overlooked when considering this group of amphibians. This leaves us with many modes of communication not thoroughly explored. Many salamanders use chemical cues as one of their primary modes of communication, yet very little work has been done with frogs in regards to this mode. Their flashy auditory calls must be quite a distraction from other forms of anuran communication.

Bruce Waldman and Phillip Bishop published a study, "Chemical communication in an archaic anuran amphibian” that was performed from 1997-2000 concerning chemical communication in the frog Leiopelma hamiltoni. This species is very plesiomorphic and uses auditory calls only to frighten predators and not in a social context. This study showed that these adult frogs use chemical communication in a social context. These frogs were shown to use chemical signals to aid in self-recognition and in distinguishing between close neighbors, neighbors living close to the frog’s home range and between frogs that are unfamiliar to them. This study did not show what function such communication would serve. It did however speculate that such communication could be used to select for non-related mates or to allow related frogs to cooperate with one another. This species rarely strays from an established home range and so to optimize reproductive output it would be beneficial to be able to distinguish between related and unrelated frogs. Similarly to birds learning the songs of their neighbors, these frogs use chemical cues to learn who their neighbors are. This allows them to properly respond to unfamiliar frogs appropriately.

The Link to this article is: http://beheco.oxfordjournals.org/cgi/content/abstract/15/1/88

Posted by: Jess Bouchard
Chemical communication is easily disrupted and easily corrupted, especially by human activities. This form of communication seems to be a fit for this species, which have a small home range and do not stray far. What impact has human activity played in the decline of this species? This species is a protected species in and around New Zealand. Is this form of communication going out of style as a primary social communication mode, especially considering the amount of toxins and waste humans dump into the environment everyday. Hopefully more work can be done to uncover other species that use a similar communication method and also concerning how this effects the overall fitness of this species in this day and age.

Baby Bats Imitate Dad's Songs

An article in Sience called "Baby Bats Imitate Dad's Songs" discusses baby talk in bats. Scientists have discovered a species of bats(Saccopteryx bilineata)in which the babies make "baby talk." Researchers have now also concluded that this baby talk is not just random nonsense noises, but is actually an attempt to imitate the songs of males with territories and groups of females. This is a rare discovery since, until recently, only birds, elephants, cetaceans, seals, and humans have been known to exhibit this "complex vocal imitation," which scientists define as "the ability to learn a call or song from a tutor."

This species of bats usually lives in groups consisting of one male and up to eight females. Each female can have one pup each year. Males guard their territories by singing songs. The adult females do not sing songs, but the pups (of both sexes) sing and make plenty of "baby talk."

According to this article, Mirjam Knörnschild, a behavioral ecologist at the University of Ulm in Germany, heard complex vocal imitations while she was studying S. bilineata. It sounded as if the pups were imitating the male's songs, sometimes almost completely. To decide whether the pups were just randomly combining sounds or whether they were actually trying to sing the songs of the male in their group, Knörnschild compared the baby talk of 17 pups ranging in age to the songs of six adult males. She found that as the pups matured, their songs became more like the male's territorial songs. Also, throughout all stages of the pups' lives, they made "buzz syllables" that matched those of the males, showing that they were actually imitating the males.

The similarities between the pups' songs and the male's songs are not just caused by genetics, because the male in each territory doesn't necessarily mate all the females in his group. This proves that the similarities occurred because the pups listened to the songs of the male. Learning these songs is essential for the male pups to be able to attain territories when they are older, and Knörnschild believes females must also learn these songs to be able to choose mates.

This article is so interesting because it illustrates the learned component of communication. A link to the article is posted below:



Posted by Sarah Benjamin (1)

Termites Eavesdrop to Avoid Bullies

When you talk about predator prey relationships between species, most of the time you think of two different species. Sometimes the predator and the prey are the same species. Take for example termites, who learn to avoid running into one another. They use communication so that they have there own section of "wood" to live in. It does't matter who is the better kind, it just matters that they never run into each other.

In an August, 26 2009 article in Animal Planet, Dani Cooper talks about Theordore Evans and his research about termites. He talks about how two Australian termite species coexist with each other. He found that Cryptotermes secundus can locate their deadly "cousin," Coptotermes acinaciformis by listening to the vibrations they make when they are chewing. Once the Cryptotermes hears the vibrations of the other one they know to go the other direction. Evans recorded vibrations of both termites chewing. When he played this for the Cryptotermes secundus they ran away from vibrations made by their "deadly" cousin, but when they heard vibrations of their own kind they moved towards the sound. If the piece of wood was smaller the response was increased. Meaning that the termites are able to how close they were to each other. So even though the Cryptotermas are less dangerous than Coptotermas, they have found ways of avoiding them.

Evans think that since we know that termites respond to vibrations, there could be away from keeping them away from our houses. That way no chemicals would have to be used and people wouldn't have to worry about termites eating their homes!

Posted by Samantha Babcock

Revision -
There was no mention of pheromones at all in the article. It just talked about how they used vibrations how chewing to tell how far away they were from each other. They mentioned in the article that they need to do more specific research about the vibrations. To find out things like what about the vibrations makes them able to communicate. Also the article only mentioned these two types of termites. But along with furthering research, Evans said he was interested in finding out if this takes place within other species of termites.

Why Dogs Bark - stephen Chiricosta





In the most recent issue of Australian Veterinary Journal, a group from the University of Queensland’s Center for Animal Welfare and Ethics did a study on their hypothesis that “City-living domestic dogs may be more prone to nuisance barking”. There study consisted of 150 dogs, (72 dogs of which came from owners who had there dogs go for nuisance barking treatments.) the results seem to show that the most likely dogs that became nuisance barkers were young dogs that were from herding breeds. They used the example of collies in the article.

Co-author of the report, Clive Phillips said, “The survey showed the greatest risk factor was the age of the dog. More than a quarter of those dogs that had been classified as nuisance barkers were less than a year old.” From this results these scientist began to thing about what other aspects could influence young dogs to become barkers. In the article Phillips says, “Barking may be caused by separation anxiety, perceived threats in the environment and sometimes to simple social interaction, canine-style. But human actions and responses also play a role.”

What the team concluded was that dogs are very loyal to their owners; this increases the likely hood of their theory of separation anxiety, also the researchers were surprised to find out that dogs bred at home were more prone to be nuisance barkers.


http://dsc.discovery.com/news/2009/10/16/barking-dogs-city.html


Question:

I notice she barks and chases cars more frequently. Was there anything mentioned in the report that draws a correlation between limited exercise (outside activities) and nuisance dogs?
Emerson Martin
Answer:
There was nothing mention in the article connecting outside activates and nuisance dogs. This article was mostly about trying to understand why City house hold dogs were considered more of a nuisance.

Question:

Would more exposure to other dogs help throughout their life so they are not as anxious in their presence throughout their life?

Answer:
This also wasn’t talked about much in the article, however it was talked about if the parent of the dog was still active in the life though the puppy’s adulthood, then statistically there was less anxiety.

Question:

Do you know if wolves or other "feral dogs" participate in nuisance barking, or is this strictly a quality of domestic dogs?

Answer:
I am sure there are studies out there regarding wolfs or “feral dogs”, however this study was only evolving domestic dogs.


-Stephen Chiricosta

Bats sing sweet love songs to each other in the night.
University of Texas at Austin
(http://www.utexas.edu/news/2009/08/25/bat_love_songs/)

In Austin Texas, researchers at Texas A&M university are interested in how male bats attract female bats at night. In an attempt to pick up lady bats in their nightly outings, researchers have found that male bats have a complex repertoire of vocal love songs they produce. These love songs have recently been decoded by the researchers.

Three years of analyzing Mexican free-tailed bat recordings has revealed that male bats sing with discernible syllables and phrases to attract females, and also to warn other male bats to stay away.

Neurobiologist George Pollak, biologists Kirsten Bohn and Mike Smotherman, and Barbara Schmidt-French of Bat Conservation International have been working with the bats. "I am amazed at the richness of the vocal repertoire that bats use for social communication," says Pollak. "Their courtship songs are perhaps the most surprising, since each song is complex and structured."

The bats use several types of unique syllables, or sounds, and they combine these syllables in specific ways to make three types of phrases: a chirp, a buzz or a trill. The males use different combinations of the three during the mating process.

These sounds are incredibly difficult for the human ear to pick up as the bats communicate at a very high frequency. The sounds are used in a very specific way, arranging syllables into patterns making up songs. Many of the bats the researchers studied were found living in downtown Austin Texas beneath Ann Richards Bridge and Kyle Field in College Station. There are over an estimated 1 million bats at both of the locations combined.

"We compared the recordings made by bats in Austin to those at Kyle Field, and we discovered they were almost exactly the same," says Bohn. "The bats in both places use the same 'words' in their love phrases."

Their results are surprising because generally speaking mammals don’t have rules to their communication patterns. Birds are well known for having complex communication patters and so are whales. This new information shows that bats are capable of unique vocalizations between other members of their species. Pollak adds, "Who would have thought that bats could have one of the most sophisticated and rich vocal repertoires for communications of all animals?"

Posted By "Nicole Breivogel" (3)

Wednesday, October 14, 2009

Scentless Flies are Desirable


Fruit flies may be attracted to the scent of ripened fruit when looking for a treat, but when looking for a mate they are attracted to the scent of nothing. Joel Levine conducted a study where oenocytes, pheromone-producing cells, were selectively killed off in the abdomens of Drosophila melanogaster(fruit flies). Without the pheromones the flies had no scent and that made them all the more attractive to other flies.

When normal male flies had their pick between females lacking pheromones, males lacking pheromones, and normal females they would pick the females and the males lacking the pheromones. Not only were males of the same species more attracted to the scentless flies, but males from three other species found the scentless females desirable.

To figure out what messages the pheromones were sending Levine and his colleagues added back a female pheromone (7, 11 HD), which is an aphrodisiac. They found that adding the pheromone did not make the flies any more attractive. Adding cVa, a pheromone that warns males to stay away, made both the normal and the scentless females unattractive to males. If both of the pheromones were added then the female chemical 7,11 HD won and the flies were no longer found to be unattractive.

7, 11 HD is not only an aphrodisiac that is able to overcome the cVa pheromone, but it also a species marker. When it was added back to the scentless females the other species of Drosophila no longer found them to be desirable.

By killing off the pheromone-producing cells and manipulating 7,11 HD and cVa Levine was able to determine that pheromones not only distinguish between sexes, but they also distinguish between species.

-Tara Quist (3)

Monarch Butterfly Uses Antenna for GPS


Many scientists have always wanted to answer the question" How does Monarch Butterfly find their ways during migration"? And the answer turned out to be their antennas. This was known from an experiment where they painted the Monarch antennas with black and record their observations. The result shown that butterflies with antennas painted black did in fact lost their ways, the one that didn't have their antennas painted navigate just fine.


Monarchs also have circadian clock in their brain that act as a time keeper which is extremely important because this will allow them to determine what time it is and the sun position. Monarchs also have a second clock in their antenna to sense light, and this was discovered by Dr. Steven M. Reppert, chairman of neurobiology at the University of Massachusetts Medical School. Dr. Reppert insisted that by having a better understanding about how their brain works also give us better knowledge of our own brain.


So, Monarch antennas are critical for their navigation, but what about their vision and smell? To answer this question, researchers performed another experiment where they painted the antennas with black and clear paints. The one that had black paint on their antennas obviously got lost while the one with clear paint were normal. What they learned from this experiment was that not only the antennas are light sensitives, but sense of smell isn’t important in helping the monarch find their way because both the black and clear paint blocked their sense of smell. Surprisingly, researchers also found that butterflies that had their antenna painted black weren’t able to navigate their way even though they can see with their eyes. This important finding helped the researchers determined antennas is more critical when it come to navigation. Butterflies that have their antennas surgically removed can no longer senses direction. Without antennas, butterflies are disoriented.


Tiffany Phan (week 3)

Dolphin Saves the Day


On the east side of North Island, one of the three islands that make up New Zealand, is Mahia Beach. This is home to a local hero named Moko. Moko is a female bottle-nose dolphin who decided to take up residence at this beach over two years ago. She is known for searching for swimmers and boats to play with and has become a local celebrity. Quite a few swimmers have been know to go out and play with Moko and have found her to have an excessive amount of playfulness. She has also been known to swim up to boats and let people pet her as well has push kayaks around with her nose. Although there are not many cases of dolphins interacting this closely with humans, this dolphin has made quite a name for herself. Dolphins are known for being very intelligent and seem to understand when someone else is in need of help.
Mahai beach has about 30 whales that become stranded on the beach every year. A field worker for New Zealand’s Department of Conservation named Malcolm Smith was told about two pygmy sperm whales that had gotten themselves trapped behind a sand bar. During each attempt to free the whales, the pair kept getting confused and would get themselves stranded again. After an hour and a half of trying to lead the whales back out to sea, Smith was about ready to give up. Moko came just in the nick of time, coming right up to the whales and leading them down the shore to a narrow opening that led to deeper water. Smith said that just before she led the whales to safety, he heard them exchange vocalizations. Since there is no known common language between dolphins and pygmy whales, it is unknown what they communicated to each other. Dolphins are known for traveling with other species of whales for protection purposes so it is very plausible that they can communicate with each other. Smith seemed almost surprised that Moko could communicate with the whales. In my opinion, if dolphins are known for traveling with whales, then I would think that they would need a way to communicate with them. Also, since they are such similar creatures, I would think that some of their modes of communication and maybe even some of their signals would be the same or at least closely related.

http://www.timesonline.co.uk/tol/news/environment/article3540973.ece
http://dsc.discovery.com/news/2009/07/27/dolphin-swimmer.html

Jenn Sears

Tuesday, October 13, 2009

Predatory Birds that Impale Prey


Impaling prey is a behavior only found in two bird species, the Northern Shrike and Loggerhead Shrike. Scientists believe this type of hunting behavior has evolved from other species of birds that wedge their prey before consuming. These shrike species are the only songbirds (passerines) that hunt other birds. They also hunt small mammals and insects. They do not have strong talons or massive beaks like raptors such as falcons and hawks do. However, they have a distinctive sharp point at the tip of its beak to tear into its prey. Once their prey is captured, they will impale their catch on a thorn, barb wire, or even branches in small bushes. When shrikes’ vertebrate prey is impaled on a sharp object they are then usually decapitated and, in most cases, the brain consumed before other body parts. Field observations confirm that the ability to impale prey develops in the young of these species in the first 4–5 weeks after fledging. They have evolved this behavior to reduce handling time of their prey and reduce any risk of injury. They are also known to hunt toxic grasshoppers. They will impale the grasshopper and leave it in a cache (storage spot) while the deterrent chemicals decompose and the grasshopper can then be later consumed. Caching is used by shrikes to demarcate territories, store food for inclement weather or periods of stress in the breeding cycle,and divide labor between the breeding pair. During the period of prenuptial display, male shrikes were observed to impale inedible objects such as rags, snail and eggshells, or even bread crusts, ostensibly to boost the visual effect of the cache. The larger the cache the higher the reproductive success of male Shrikes.

Posted By Carlos Varela (week 3)

Parent- offspring communication is a common topic of study for signal observation in many animals. Although it is not so common in reptiles, these types of behaviors are displayed readily in birds and mammals. All crocodilians make a “hatchling call” both when inside the amniote egg and as a juvenile.

Much like the group project we recently completed, the authors of this study were interested to determine whether there were physical characteristics of the individual’s calls that mother crocodiles could use to distinguish their young. The authors found that although individual recognition is not clearly observed in Crocodylus niloticus, the acoustic signals may serve as an indicator of mood and level of development. These signals can aide in the mother’s ability to protect the young in the best way possible for the context it is provided.

This study does show that although individual vocal recognition may be unlikely, the calls that individuals may produce will change with maturation in the juvenile stages. With the “still in egg” call that consists of a swift up-sweap, and the after hatched “distress call” involving both the up-sweap and a down-sweap in pitch. This method also shows that fundamental frequencies of these calls decreases with a juvenile crocodiles age. Instead of using Raven to do the acoustic analysis, this study utilized two software programs, Syntana and PRAAT.

posted by: Jeremy Ross

And they Lived Happily Ever After....


I'm not a huge fan of spiders, but I found this to be pretty cool (seeing that you have probably learned about this general topic in some biology course or another like I have). We all know (or you will now) that female spiders eat their mates after copulation. It has just been announced that there is a "hippie" spider that is vegetarian and doesn't even live on a web. This means she doesn't eat her mate!

The species is called Bagheera kiplingi, and it is from South America. It is one out of 40,000 species that acts the way it does. Its diet consists of wild acacia plants! The only obstacle with this, is that they first have to get past ants guarding the food on these plants. Eating plants puzzles scientists because spiders are not physiologically built to be vegetarian, but B. kiplingi eats veggies whole.

Instead of living on a web, this spider hangs out on leaf buds mostly, so there is no need to catch any prey on a web. They don't seem to be having any troubles. This is nice for the spiders because all of it's energy isn't wasted on making webs for the purpose of prey catching.The only time it will use its web making is to make little nests for its young.

This interesting way of living and I wonder what type of communication goes on between this species of spiders. They first need to find a way to get the food from the ants. Do they communicate in this task? The female does not eat her mate, so does this mean that they stay together? Does the male still bring the female a nuptial gift? This communication could be much different than the 40,000 other spiders that exist and will be interesting for researchers to figure it out.

Update: I am assuming that they avoid all "meaty" snacks because the acacia plants are so abundant in that area. From reading the articles, I understand that they only eat that type of plant (the bugs from it). No other research has been done to find out physiologically how they have adapted such a way to be complete herbivores. Maybe this is helpful that she does not sacrifice her mate because he can be around to help with young. But then I wonder, this could be helpful, but all 40,000 other species can handle raising them on their own. More updates will come if I find anything else about this topic!

http://www.timesonline.co.uk/tol/news/science/biology_evolution/article6869475.ece

Posted by Alyson Paige (week 3)I

We don't have to talk to be a couple!



Breeding pairs of emperor penguins do not have breeding territories. Thus, they protect their expecting mates by staying with them until the egg is laid and transferred to the male for incubation. It is during this period that mating penguins refrain from verbal communication, so that unpaired penguins do not disrupt them. During the incubation period, males must huddle with hundreds alike to conserve energy and heat before breaking up and huddle again with other penguins. It is also during this dispersion that mates may get separated. With the inability to verbally communicate, how are they able to find each other among the chaos? A study conducted by André Ancel and colleagues from the Institut Pluridisciplinaire Hubert Curien à Strasbourg in France has found that pairs of breeding penguins stay in their partner's visual field at all times.This was observed by attaching data recording devices on four breeding pairs from a colony of 3,000 penguins. This study concluded that pairs huddled close to each other 84% of the time, with each leaving the huddle within minutes of each other. This leaves almost no room for separation.

Source:
http://www.nytimes.com/2009/03/17/science/17obhuddle.html?_r=2

Posted by Vanessa Raphaël (week 3)