Amphibious Communication with Sound in Hippos

Hippos are capable of making sounds in air and in underwater. In an amphibious position (eyes and nostrils above water but mouth and throat below), they are able to send communication signals onto air and underwater at the same time.

The transmission of sounds passes through different paths. For sounds passing on air, the position above water passes through nasopharynx, continuing through the nostrils to air. Underwater sounds are made from other parts of the pneumatic system that produce sounds, but mainly by other ways such as from the larynx through the prominent roll of fat and skin in the throat. The acoustic structure of the underwater and surface sound is different. The underwater has higher frequency compared to the surface frequency.

Hippos need to be able to communicate under and above water in an amphibious position. Studies have shown that they have a working technique of transmitting amphibious sounds. However, the study of hippos hearing anatomy is still in process and is not fully understood.

For more details on this article, please visit the link below:
http://www.sciencedirect.com.silk.library.umass.edu:2048/science

Posted by Fatema Farhana (week 1)

ANCIENT "MEGA" SHARK NURSERY FOUND IN PANAMA!

The Megalodon has been extinct for awhile but a giant nursery for these huge predators has been found. These 49 feet plus sharks from the prehistoric neogene period are undeniably the biggest predator this planet has seen. Sharks so big that they fed on whales would have offspring the size of a great white. These offspring nursed together in two known areas South Carolina and more recently discovered Panama.

Scattered teeth have been found on the shores of the Caribbean Sea in Panama. These teeth are the size of our modern day Great White sharks; yet these shark teeth are not fully grown they are merely adolescent Megalodon teeth. In the neogene period these fully grown massive predators would have 6 inch long teeth! 6 inches long! May I now direct your attention to the terrifyingly amazing picture which would be a surfers fate.

This find was led by Catalina Pimiento of the University of Florida in Gainesville. From reading this article it seems as if Pimiento was trying to make a claim that his find is the first of its kind. The nursery found in South Carolina contained adolescent and fully grown Megadolons along with whale skulls. While the nursery he found contained only adolescent teeth. In this article Pimiento was referenced to saying that he thinks it is unlikely that adolescent Megadolons would feed on whales since most adolescents do not require much food. Was the nursery Pimiento found the first of its kind? Was the South Carolina nursery not really a nursery? In my opinion Pimiento has a legitimate claim if he can back it up with more solid facts than that!

In any case, I for one am happy these magnificent monstrous beasts are no longer alive to prey. Let us stick to our more moderate set of jaws, the Great White. Plus, I like surfing!

Original Article found at http://dsc.discovery.com/news/2009/09/29/megalodon-nursery.html.

Posted by “Alexandre Bourdois” (1)

Communicating with Cows Increases Milk Production

Animals communicate in a variety of ways. They have different sounds, scents, and postures that portray different messages. While communication occurs within a species, it can also occur between different species. Communication between species can have benefits.

Dairy cows face pressure because they must produce milk for their farmer daily. Research suggests that one way to get more milk out of anxious cows is to name them. Cows that have names produced up to five percent more milk. By giving a cow a name, a farmer gives her more attention, and treats her as an individual. A cow that has a name is more relaxed than if it is treated as just another number. If a cow is stressed, elevated stress hormones like cortisol reduce milk production. Cortisol interferes with oxytocin, which increases milk production. Cows that are anxious also stomp and kick, which makes milking harm, and could also be lethal to the farmer.

A study was done to show how a cow's relationship with people affects her behavior and milk productivity. On farms where cows had names, they produced an average of 258 more liters of milk in ten months. Also, if young heifers got extra attention at a young age, they produced more milk later in life.

Other studies have been done with other species of animals too. Nervous chickens will lay fewer eggs, frightened pigs grow more slowly, and scared trout eat less. By giving these animals more care and attention, both groups can benefit. People can communicate with their animals to give them a better quality of life.

Emily Crete (week 1)

original article can be found at:

http://dsc.discovery.com/news/2009/02/05/cow-milk-name.html

King Penguin Chicks Need to Communicate to Survive

Read the article here.

King Penguins chicks must do one thing in order to survive in the harsh Arctic climate: communicate. When a chick is old enough to self-thermoregulate, both parents leave the chick in a specific "rendezvous zone" with a group of chicks. It is of the utmost importance that the chick stays there. The parents will return to feed the chick and with several hundred identical chicks in a colony, the only way to know which chick is the right one is through sound. Parents and chicks are extremely efficient in identifying each other based on individual vocalizations (which are unique to each bird), but this is only successful when the parent is within 8 meters of the chick (the hearing distance of an adult King Penguin). If a chick strays or is displaced further than 8 meters from the "rendezvous zone", then it will not be fed and will die of starvation.

Chicks could be displaced for a number of reasons, including weather and disturbances from predators. It is vital that a chick has the ability to find its way back to the "rendezvous area" after being displaced for any reason. Thus, they have developed the ability to find their way back. In an experiment by Nesterova, Mardon, and Bonadonna, several chicks were taken from their "rendezvous zone" and released 100 meters south of their colonies. Two experiments were performed to assess what senses the chicks used to relocate their "rendezvous zones".

The first experiment was done in a large arena that had a barrier that prevented a view of the colony. The chicks were released and it was recorded where the chick spent the most time in the arena. It was noted that the chick spent most time in the northern half of the arena (closest to the colony), and it is hypothesized that this is because of olfactory and auditory stimuli carried by the wind from the colony.

The second experiment involved letting the chicks go and observing where they walked. Most chicks went directly back to their "rendezvous zones" and stopped within meters of where they were captured. It is hypothesized that this is because the chicks recognized their landscape and the position of the sun to orient themselves and figure out where their "rendezvous zones" were located.

More experiments will need to be performed to better understand how the chicks find their way back. Is auditory or olfactory stimuli more important? Is this a learned or innate behavior? With the ground work laid down by this experiment, many more questions surface, but new experiments can be created to answer them.

In order for a King Penguin chick to communicate with its parents, it must be in the specific spot where it was last fed. If displaced from this spot, the chick must find its way back in order to survive. The experiments performed in this article demonstrate that at a young age chicks know their surroundings well enough to find their way back after displacement. They know the importance of communication.

Posted by "Tricia Carlson" (1)

Deceptive Squeak Invented by Orangutans

Animals communicate in many ways and for many reasons. One of the most common reasons an animal communicates is for its own safety. Animals can communicate with members of their own species or even with predators when they sense a threat.

The article "Orangutans Invent Deceptive 'Kiss Squeak'" by Jennifer Viegas for Discovery News discusses a study recently published in Proceedings of the Royal Society B. Researcher Madeline Hardus from the Behavioral Biology Group at the University of Utrecht and her colleagues found that, when threatened, orangutans produce a "kiss squeak" sound that makes them sound larger than they actually are and, therefore, more intimidating.

The researchers recorded wild orangutan kiss squeaks at Central Kalimantan in Borneo, Indonesia. The orangutans can make the sound a few different ways. They can make it themselves with a sharp intake of air through puckered lips or they can modify the call by making it against their hands or using leaves stripped from twigs. This study shows that the orangutans can use a tool to modify the sound and provides evidence as to how and why animals modify calls. The orangutan is the only primate that makes the kiss squeak noise, and this call is the only known modified call made by any primate.

Orangutans sometimes use one hand to make the leaf-modified kiss squeak while using the other hand to throw things at predators, which is evidence that this call is part of a defense mechanism. After analyzing the recordings of kiss squeaks, the researchers found that the hand-modified and leaf-modified calls had lower maximum frequencies than the kiss squeak made using the mouth. The leaf-modified squeaks had the lowest maximum frequencies of the three types and did not change the sound in any other ways. The researchers believe the lower-frequency squeaks are meant to fool predators who can hear but cannot see the orangutan into believing the orangutan is larger than he actually is, since larger animals tend to produce lower-frequency sounds than smaller animals.

The article explains that there have been increasing threats to the survival of orangutan populations over the years. Sumatra and Borneo are the only two islands the orangutan still inhabits. Hardus explains that the modified kiss squeak probably started with one individual through trial and error and eventually caught on with other orangutans as a mode of protection. The study by Hardus et al. proves that orangutans' communication skills are more developed than previously thought.

A link to the Discovery News article "Orangutans Invent Deceptive 'Kiss Squeak'" by Jennifer Viegas is provided below:

http://dsc.discovery.com/news/2009/08/05/orangutan-kiss-squeak.html

Posted by "Sarah Benjamin" (1)

Dolphins Exhibit Communicative Patterns Displayed by Humans

Most would agree that communication seems relatively species specific. In other words, understanding the complex sounds and behavioral actions in other animals is always a tedious task. Still, with the ideas put forth in evolution, we must assume that not only do the ways in which animals communicate stem from behaviors of common ancestors, but also are based on using energy efficiently. This assumption can be solidified by comparing the complex communication behaviors exhibited by dolphins and humans.

As explained in the August 11th 2009 Discovery news article, Dolphin Speak Relies on Brevity , by Emily Sohn, Dolphins display a communication trend that not only resembles trends in human language but also accounts for communicating in an efficient manner. When humans converse, it is obvious that the words used most often are short, such as “the” or “I” , making it easier to get our points across without having to use excess energy. It has been found through field studies done by Lusseau and Ramos Ferrer-i-cancho , that dolphins exhibit this same trait in their non-vocal behaviors. Although these marine mammals have many complex communication behaviors, the simplest actions are those that were observed and used by the dolphins the most. This leads to a couple conclusions. First of all, as described by Sohn, the idea put forth by many scientists when referring to human languages, called the “law of brevity”, can now be related to another species. In addition, since humans and dolphins diverged from a common ancestor millions of years ago, it may be safe to say that these characteristics are an example of convergent evolution due to efficient usage of energy. Lastly, a possible idea could be that even the most basic communication used before the evolution of mammals was structured in discrete units, and complexities were built from these units as needed over time.

Sohn’s article also poses many other underlying ideas, such as why animals may use the same behaviors to represent different signals in varying contexts. In addition it shows the commonalities that exist between animals of different species.

In conclusion this is a pretty significant breakthrough that should be looked into further. Not only does it propose a new idea about dolphin communicative behavior, but it also shows that complex language made up of short behavioral units is not just a human trait. This could lead scientists to more similarities making it easier to understand how species rearrange their intricate signals, which in turn could aid in discovering the meanings of these behavioral cues as well.

Jackie Connolly (1)

Why the Swamp Sparrow is Hitting the High Notes

Why the Swamp Sparrow is Hitting the High Notes
Science Daily

Studying animal sounds and signals almost gives humans a look into the past of how our own communication abilities evolved over time. A good example of this is how humans and animals raise their voice when they are expressing aggressive communication, but why are some animals louder then others when they are aggressively communicating.

On January 12, 2009,Adrienne DuBois, a graduate student in the college of Arts and Sciences, conducted a study on aggressive communication at the University of Miami. DuBois’s study showed that the Swamp Sparrow has the ability to emit songs that are extremely difficult to produce during hostel situations. She believed that this meant that the Songs Birds used sophisticated vocal performances as Signals in aggressive communication.

At the end of the article Steve Norwicki, a professor at Duke University, said “By understanding what animals do in their natural environment, we get a glimpse of what their brains can do," …"In a broader sense, we can make assumptions about the way the animal brain develops to support a complex communication system."

This study shows that the Song Sparrow can communicate a threat by exerting a physically difficult high frequency. This ability to escalate their vocal performance shows scientist that the Song Sparrows brains are more sophisticated then originally believed.

Journal reference:

1. DuBois et al. Swamp sparrows modulate vocal performance in an aggressive
context. Biology Letters, 2009; 1 (-1): -1 DOI: 10.1098/rsbl.2008.0626

http://www.sciencedaily.com/releases/2009/01/090109125636.htm


-Stephen Chiricosta

Elephants Use Low-Frequency Sounds to Communicate

The Elephant Listening Project (ELP) uses acoustic monitoring to evaluate the abundance and health of elephants living in the dense African forest.

Bioacoustics Research Program (http://www.birds.cornell.edu/brp/research/animal-communication-research )

Researchers at Cornell University working on the Elephant Listening Project are studying the acoustical patterns of the Asian, the African savannah, and African forest elephant. All three species of elephant make calls at low-frequency that are lower than human’s ability to hear (20 Hz). This type of infrasound, however, is very powerful and breaks down very little over long distances. This allows elephants to remain in communication with each other over great expanses of forest or savannah. Elephants within a family can remain in contact with one another up to 4 kilometers apart.
Interestingly, the diversity of elephant calls is apparently similar between all three species of elephant. This type of familiar low-frequency communication allows elephants to identify and coordinate with one another while foraging. Based upon the behavioral context, researchers have revealed multiple call types and that the majority of these calls are made by females. Calls are used to coordinate a larger group of individuals or for reproduction. These calls are differentiated by recurring ‘fission’ and ‘fusion’ of related individuals structured around adult females in the group. Using this communication is critical to maintaining the family as it moves throughout a forest or savannah.
This is an example of the different types of rumbly sounds made by forest elephants. This was recorded at the Dzanga clearing in the Central African Republic by the ELP team. The orange line shows the limit of human hearing. Elephants can produce sounds that are both audible and non-audible to humans.
The researchers mainly focused on acoustical data for their study, but made note that it is also important to recognize that elephants also greatly use smell. Pheromones are an important part of elephant particularly communication for mating. However the long distance communication allows for elephants to pair up.
The life of an elephant is long lived and they maintain many complex lasting relationships. Their acoustical communication patterns are similarly intricate. We are still at the forefront of understanding this system but researchers believe information including emotive state, physical characteristics, intention, and perhaps even abstract concepts are communicated using these deep low-frequency sounds.

Posted by "Nicole Breivogel" (1)

Saturday October 3rd, 2009

According to the study by Cornell University, the task of studying the low frequency communication of elephants in a dense forest environment seems daunting and would likely be full of difficulties. The variation in the habitat in that type of area wold make it difficult to conduct research.

These low frequencies are believed to be used because of the types of environments that forest and savanna elephants live in. Females are able to distinguish one another from their calls.

Eephants are also very olfactory animals - they use their sense of smell to decode an entirely separate, but overlapping, language based on pheromones. Pheromones are probably particularly important when elephants are communicating about their readiness for mating. But long distance communication using infrasound likely enables male and female elephants to come close enough together to find one another and allow the shorter-distance chemical language of pheromones to come into play.

Pandas Using Communication to Choose the Best Mate

In the animal kingdom the most important aspect is the survival of one’s genes and preserving those genes for future generations. Through the ideas of natural selection it is only those who are most “fit” that will succeed in preserving their genetics and passing them on to further generations. There are many different things that make an animal fit and most desirable for mating and preservation of genes dependent of species. In the Giant Panda for example, these specific characteristics that make one panda more desirable over another is for a male to be big and strong and in a female to be older and more experienced for breeding. It is very important that these particular successful traits be communicated through the sexes to help increase the chances of successful mating and thus preservation of their genes. Those that don’t tend to fit these trends will over time be phased out through unsuccessful breeding through the theory of natural selection.

In the September 14, 2009 issue of Discovery News, Jennifer Viegas writes about the specific vocalizations used in the Giant Panda species that communicates specific information valuable during the breeding season. Scientists Benjamin Charlton, Zhang Zhihe and Rebecca Snyder recorded the specific “bleat” vocalization of the panda. This bleat vocalization is one that is common to both sexes but is more prominent during the mating season. A total of 18 pandas were recorded, 9 female and 9 male ranging from ages 6 to 21 years. Data on age and body size and weight were recorded for each panda as well. Acoustical analysis was made of the recordings using special programs and interesting results were concluded. The scientists were able to determine through these acoustical analyses that both the male and female panda had distinctive voices, unique to the male and female sex just as the human male and female sound differently. This is a valuable piece of information needed during the breeding season to identify the sex of the panda over a distance to help avoid conflict between members of the same sex. The male bleat was determined to communicate information about its body size to the female while the female’s bleat communicated her age to the listening panda or pandas. These are both very valuable pieces of information to communicate to the members of the opposite or, in the case of the male, to members of the same sex. The male is most interested in a female that is experienced in breeding and the female is the most interested in the biggest and most husky male, the combination of these two characteristics lead to a greater chance of a successful breeding and rearing of the most successful young. It is also valuable for a male to communicate his size to help to avoid risky conflict between another male that may be smaller or larger warning the smaller of the two to stay away.

It is very important to be able to have a successful breeding and rear the most fit young to ensure the preservation of your genes through future generations. In the example of the panda they are able to communicate these desirable characteristics to help make these decisions. Through communication they are able to convey that they are a large, husky male or that they are an aged and thus experienced female. These individuals will in turn be the most successful during breeding season and the most successful in preserving their genetic makeup.

Posted by "Jessica Abu-Hijleh" (1)

Startled Pigeons Whistle with their Wings

Animals communicate in very different ways and for different reason. Most of the communication is vocalizing from a signaler to a receiver. But that is not the only kind of way species communicate with each other. Take for example Crested Pigeons, who use their wings to communicate to other pigeons. Normally when they are flying their wings are making a whistling sound, but only when the sound becomes louder and quicker do other pigeons pay attention.

In the September 9, 2009 article in Discovery News, Michael Reilly talks about a study done by Mae Hingee and Robert Magrath to prove this quality in pigeons. In there study they showed that these pigeons emit a whistling sound from their wings when flying, but when they are flying out of fear the beat more rapidly and harder. They recorded the sounds of the bird flying happily around and than they added in a decoy. The decoy was a hawk and when the hawk was added into the picture the pigeon started flapping its wings more rapidly. When they played the sound back it showed that other pigeons weren't responding to the pigeon happily flying around, but when it started to flap at a quicker and harder pace the rest of the birds fleed. They concluded that the sound and tempo of the whistle was how the other birds knew when the signaler was takig off in fear or not.

This is a very important signal that the pigeons use to communicate with each other. It helps them all know when they are in danger. Also it is distinctive enough that they always recognize it so they can all stay safe. After reading this article I now know why pigeons all fly off together at the same time.

http://dsc.discovery.com/news/2009/09/02/pigeon-wing-alarm.html

Posted by "Samantha Babcock" (1)

THE ARCHOSAURS: CHATTING about SURVIVAL

The Archosauria are represented by only two extant groups of animals: The crocodilians and the aves. Most people seem shocked to learn that, in extant species, birds are most closely related to crocodilians. These two groups diverged sometime in the mid to late Triassic, so it is of no surprise that upon initial glance these groups appear so drastically different. Birds are so highly modified and crocodilians seem frozen in evolutionary time. However, similarities especially arise when one considers strategies each group utilizes to ensure that their young are able to reach maturity and thus pass on their genetic lineage. Crocodiles, alligators and their relatives are in the paraphyletic clade the reptiles; most of whom do not perform parental care and lack vocalization. However, crocodilians, like birds, build and tend their nests, protecting them from predators and stay with their young after they hatch and can function on their own. Crocodilians also use vocalization as one of their main means of communication, which is unique among reptiles. Not only do these extant archosaurs use vocalization to communicate throughout their lifetime to survive, they communicate even before hatching from within the confines of their egg.

An article posted on Biologynews.net on June 23, 2008 reports on a study concerning pre-hatching calls in the Nile Crocodile, Crocodylus niloticus, preformed by researchers Amélie Vergne and Nicolas Mathevon of the Université Jean Monnet in France. This experiment is one of the first of its kind to collect data that supports that pre-hatching calls have meaning and play an important role in survival. The study was comprised of a series of “playback” experiments, which used recorded calls of juvenile crocodiles to analyze behavioral responses from both siblings and mothers. More often than not the groups of eggs who were played the recordings would respond, move and even hatch within ten minutes of the initial playback. The eggs in the mothers’ nests were removed and replaced with a speaker. They were also played the recorded calls and eight out of the ten mothers responded to the calls by digging at the nest.

The call of pre-hatched baby crocodiles is reminiscent of the familiar chick “peep” in which most people are familiar. Crocodilians have a small vocabulary in comparison to birds, but considering they lack vocal cords, they get the job done. To hear different crocodile calls, including the endearing hatchling call, a fun website to visit is Adam Britton’s “Crocodile Talk” webpage. There you can listen to short clips and even see some spectrograms of selected calls, which gives an idea of the selected call’s intensity.

Vocalization is an important means for survival for both birds and crocodilians. By being able to communicate to your siblings while still in the egg, it is possible to synchronize hatching and thus out number and overwhelm predators. When combined with parental care, vocalization can trigger the parent or parents to prepare to protect their offspring while hatching and through their juvenile period. Parental care greatly increases the chance that these offspring will reach adulthood and thus reproduce and continue the genetic legacy of their parents. Many factors play into the success of the archosaurs and their survival throughout their long life history. Perhaps the use of vocalization as a means of communication beginning pre-hatching has contributed in the success of the crocodilians and birds, a success that has preserved the group of animals most closely related to the dinosaurs.

posted by: "Jess Bouchard" (1).

First Blog

Here is my first blog post.