Study Shows That Sabertooth Tigers Played Well With Others

A research team from UCLA and the Zoological Society of London believes that Sabertooth tigers were social predators. The study compared the responses of modern predators to those of the ancient feline as preserved by the Rancho La Brea Tar Pits in Los Angeles.

Researchers played back recordings of distressed herbivores in the wild and took note of the numbers and species of the predators that came to investigate. It was found that, in the case of large predators, social animals were sixty percent more numerous in their attendance. This frequency of the ancient feline predator fits the modern day relationship when compared with the other large predators found in the tar pits.

The results of this study suggest that the Sabertooth Tiger has less in common with its modern namesake than one might expect. Most large cats are solitary creatures, further differentiating the Sabertooth Tiger from modern feline behavior patterns.

The full article is available here.

Posted by Allison Cornell (7)

White tailed deer, social heirarchy and behaivoral cues can lead to a more sucessful hunt (if you so desire)

White tailed deer (Odocoileus virginianus) are common throughout most of North America, commonly seen by people in their backyards, from the seat of their car or deep in the heart of the woods while trying to mimic calls and smells in an attempt to lure them into the range. Many people find these animals beautiful and feel a sense of relaxation when they see one, it is seen as a glimpse into nature, a symbol of the true brilliance and beauty that surrounds many of us everyday, a beauty that we often forget about. Although yes they are beautiful, but since deer have had the ability to feed off of many gardens and their natural predators have been disappearing their population numbers have been increasing. Therefore it is the job of us humans to take this role as population control agents.
In order to make ourselves better and more efficient at hunting and controlling population numbers we must understand first the behavior of the prey we wish to catch. As it turns out white tailed deer have a myriad of communicational mediums the current methods that we have identified are visual, vocal and olfactory. Visual responses to a potential threat elicit a stereotypic response of cocking back both ears and erecting the hair on their necks, adrenaline is then released into the blood stream in case that the animal might have to flee. Often they will then stomp on the ground in an attempt to make the potential threat move, so they can then see if the threat is real and an actual threat, this behavior also alerts the rest of the herd (if they are in a herd) that there is potential danger.
There have been six recorded stereotypic auditory responses of the white tailed deer; each is specific to unique environmental changes. an alert snort made by both sexes, a distress call, vocalizations between mother and fawns are commonly heard, grunts made by bucks when trailing a potential does estrous scent, and two types of threatening snorts. These calls when made in conjunction with visual cues can lead to a lard array of signals that deer can use to communicate with one another.
Olfactory signals can better improve the communicational ability of deer’s. One observable scent secretion is the release of scents from the tarsal glands has been observed to alert other deer’s in the area of the imminent danger. In deer the presence of Inter-digital glands have been observed, and can lead to individual identification. The foot stomp is believed to release these chemicals and alert other deer as to who they are. There are many glands that assist in individual identification of many male bucks some of those being lachrymal gland, the metatarsal gland and a gland located on the forehead. All of these have functions unknown to us, although it is believed that they function to either alert other bucks that they are in the area, or to detect vibrations in the earth, although their function still remains a mystery. Finally bucks have a gland called the Jacobs gland, its function is to help them find and follow the estrous trail left of female does. Olfactory cues are an essential part to the communication of deer, although there is still much more left to be discovered and learned about these cues.
Bucks have one last type of communication, that being their ability to scrape and rub trees with their antlers, the function of heavier rubs against trees has been found to be a correlation with the size and age of a buck. Naturally a larger animal is going to be able to remove more bark faster; this action is thought to be a territorial marker to other bucks in the area. Many times bucks will be deterred from sparring based on the size of another rub close by, this may lead to smaller bucks rubbing larger areas in an attempt to fool other rival bucks into thinking that they are larger then they really are.
In essence it is essential for men who wish to hunt and pursue game animals to know and understand the behavior of deer’s if they wish to be successful.

http://www.huntingpa.com/Deer%20behavior.html

posted by Joe Alonzo

The Amazing Lyrebird

There is an amazing species of bird that resides in Australia. It is capable of mimicking several other birds and animals. The bird I am referring to is called the lyrebird. They are known for their ability to mimic all sounds in their neighborhood, a truly amazing talent.

To secure a mate, lyrebirds create a territory and sing and dance. Females choose mates based on how elaborate their songs are. The more songs a male lyrebird knows, the more females he will have to choose from. Roughly eighty percent of a lyrebird’s song consists of expert mimicry of other birds and animals. Their mimicry is so extraordinary, they are known to mimic the occasional chainsaw, car alarm, baby crying, dog barking and camera shutter.

Check out this video of lyrebird mimicry on YouTube.

Although they are capable of learning many songs and noises, many of their songs are learned by mimicking local bowerbirds, or from each other.

If you are interested in learning more about these birds, please check out these sites:

http://www.uq.edu.au/berg/lyrebirds/index.html

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1686190

http://www.environment.nsw.gov.au/plantsanimals/Lyrebirds.htm

Posted by: Michele Copeland (7)

Cribbing: not just a stable vice?

photo credit John O'Leary

Cribbing (or crib-biting) is a stereotypic behavior seen in domestic horses. It has been an issue of debate in horse owners whether this vice is harmful to the animal or just annoying to everyone else. The action is described as a horse pressing his teeth onto a (usually) wood surface, leaning back and gulping in air into his throat often giving an audible grunt. Many problems have been found and disproved for this behavior but often its neural and learning connections weren't really considered.

Researchers from the University of Southampton in England have conducted a study dealing with the connections of cribbing and learning in a reward based system. They used four horses known to crib and four who did not exhibit the behavior. All were kept on the premises in similar conditions. Each was taken into training sessions to become familiar with the testing apparatus, which included colored lights and metal plates. The idea was that by pushing the plates with their muzzles the horses could get a food reward. Different lights were lit to signal which plate should be pressed for more immediate reward. After this initial training each horse was tested three times over three days, the non-cribbers were able to make decisions and get the rewards, progressing each time. The cribbers were not able to make progress in learning the patterns, and showed no progress over the sessions.

It is known that cribbing is related to a dysfunction of the dorsomedial striatum (other vices are connected to this as well) with these results it is clear that more research is needed, but that this dysfunction could be connected to learning problems in horses with stereotypic behaviors. Owners of cribbers might want to stop putting so much stock in stopping the behavior and think more about their training schedules, especially if they have been finding difficulties in certain areas.

posted by: Erica Damon (7)

Longest Non-Stop Flight

Imagine you are taking a plane from Alaska to New Zealand. Now imagine that you are told you have to ride a stationary bike for the entire trip, oh and you can't eat or drink anything. Surely no human could ever prefform this feat, but the bar-tailed godwit could. The bar-tailed godwit live in New Zealand and in Australia and in March of each year they start migrating across the Pacific Ocean towards China, and eventually to Alaska. It had previously been believed that the godwits return flight home was nonstop from Alaska, all the way back to New Zealand because of the lack of bird sightings in Asia in the fall. Recently, satellite tags were placed on several of the birds, finally revealing the flight patterns. Some birds are able to make the 7,200 mile trip nonstop from Alaska to New Zealand. One bird, named E7, completed this journey in only 8 days.

Not much information was given on how the birds are able to navigate across the pacific ocean, and the birds are somehow able to coordinate their departure with the low pressure systems which give them some lift. So why would these birds choose to fly straight home without any breaks? It is thought that the birds do this to avoid predators, and possibly avoid disease. Also, the more direct route is faster. There must be some reason that the birds have evolved to migrate the way that they do, and it seems that only the birds whose genes are fit enough to make the migration would be passed on. While the godwits are in Alaska in the summer, they hatch and raise their young and fatten up on clams. The birds are said to gain so much weight that they look boxy when they leave for their trip home. Also, because the birds don't use their guts to feed during the flight, their guts shrink to allow more room for fat and muscle. I think it is amazing that the birds can even make the migration up to Alaska and still have enough energy and fat reserves to be able to rear and raise chicks.

Bar-tailed godwits mature at age three or four and can live to be over 20 years old. These birds are also quite small, weighing 200-400g with a wingspan of 70-80 cm. The study is done by the USGS along with many other scientists around the world. The migration tracks can be found on the USGS website.

Edit:

Most Godwits will fly nonstop on their return migration, but a few who cannot make the journey are known to stop in the Solomon Islands and Papua New Guinea. It seems to be more advantageous for the birds to fly non-stop as they can avoid predators and diseases from making unsheduled stops along the way. Stopping to refuel would also be out of their way and could cause them to expend even more energy searching for food. The birds spend the winter in New Zealand where there are very little predators and they migrate to the Kuskokwim Delta, the largest in the world, near Alaska where there is a rich food supply. The death rate is unknown, but it is believed to be low as the population of 100,000 Godwits has been stable.

The birds leave in late August for their migration north, and return in late September, always departing with favorable tail winds. I couldn't find any information on how fast the birds fly, but I did out the math. If a godwit can fly 7,200 miles in 8 days, then that means it was flying 37.5 miles/hour! This seemed fast to me, although they are catching the tail winds, so this might help to give them a lift.

I would also thing the birds would be too full to fly on such a full belly, but somehow they do it. I wonder how the birds evolved this way, and even knew that there was food so far north in the first place to decide to fly so far. I think they're a facinating little bird. I found the answers to some of your questions here.

Posted by: Rachel Carboni(7)

Silk the New ADT?

Metalmark moth caterpillars, Brenthia monolychna, build protective shelters out of silk on the leaves that they live on. According to this new research these caterpillars can detect tremors in their webs caused by different objects, previously a behavior only known to be present in spiders. However this new study has found out that these caterpillars are able to build a “security system” with their shelters, including an escape hatch.

The study suggests that they are using the threads in the silk shelters like tripwires, which will notify the moth caterpillar of any disturbance that occurs. In case of an intruder, they have an escape hatch. These escape hatches are small holes beneath the shelters that the larvae made during the construction of the shelters.

Jadranka Rota and David Wagner set up an experiment in which they videotaped the behavior associated with different disturbances. They brought eighteen caterpillars into the laboratory, allowed them to spin their shelters, and half of the shelters were taken away. They then proceeded to tap the silk strands of the shelters or the area where the removed shelters were once connected. They also tapped the edge of the leaves and the caterpillars themselves in order to see if there is a different response. When the silk strands or the caterpillars were touched, the caterpillars escaped through their escape hatch, while when those areas where the shelters were removed were tapped, the caterpillars did not react. This suggests that they do in fact have a “security system” in place, protecting them against most danger.

The researchers are hoping that this study will lead to clues on the evolution of the animals that detect intruders with silk. This study has shown that spiders and caterpillars had independently evolved the ability to use their silk as a predator detecting system.

Posted by Katie Cole (7)

Amazing African Elephants

For as long as I can remember I have had a fascination with elephants. While they are all interesting creatures, I found through some simple research that the African elephant has some truly amazing characteristics. The African Elephant is the largest land dwelling mammal, and somehow manages to consume nearly 5% of their body weight in addition to drinking 30 to 50 gallons of water per day! (AFW: Wildlife: Elephant).

These elephants travel in small herds led by a matriarch. However, they “keep in touch” with relatives. “Several interrelated family groups may inhabit an area and know each other well. When they meet at watering holes and feeding places, they greet each other affectionately” (AFW: Wildlife: Elephant). The elephants also communicate through low-frequency sounds (too low for humans to hear) which allows them to be able to communicate from 5 to 6 miles away! They also have a unique way to communicate when a predator is visible. “Elephants communicate with an ear-splitting blast when in danger or alarmed, causing others to form a protective circle around the younger members of the family group” (AFW: Wildlife: Elephant). Not only are these elephants attentive, caring parents to their young, they also care for the offspring of other African elephants. “An orphaned calf will usually be adopted by one of the family's lactating females or suckled by various females. Elephants are very attentive mothers, and because most elephant behavior has to be learned, they keep their offspring with them for many years” (AFW: Wildlife: Elephant).

It may not be everybody’s “thing” but I could go on for pages about the fascinating behaviors of the African elephant. If you want to learn more check out these articles!

http://www.awf.org/content/wildlife/detail/elephant (original article)

http://www.wildlifeafrica.co.za/elephantbehavior.html

http://news.mongabay.com/2008/0811-elephants_wcs.html

Posted By: Ericka Adey (7)

The "Sloth" of All Sloths---Not Made Out To All It's Supposed To Be?

We have all used or heard the word "sloth" thrown around in a derogatory manner; the "sloth" we are so familiar with is a notorious reference to the slow and lazy impression we get from the species. In fact, many characteristics of the sloth do seemly shape our perception of a "sloth"---it is the slowest animal on the planet (with the speed of 5ft/min), it spends its days hanging from the trees and, because it cannot walk, only descends to the ground about once a week to defecate and urinate, and snoozes for over 16 hours a day.

Although the previous statement is valid for the most part, a recent study shows that the last trait---that the sloth sleeps over 16 hours/day, is anything but. By monitoring the brain activity of sloths found in the Panama rain forest, scientists were able to conclude that sloths only slept for an average of 9.6 hours a day, while other animals like pythons sleep for 18 hours a day. According to Dr. Neil Stanley, an expert in sleep disorders at the Norfolk and Norwich University Hospital, UK, the study on sloths that previously assumed sloths slept for 16 hours a day was faulty on the basis that it was performed with sloths under captivity: "It's intuitive that animals would sleep less in the wild than in captivity - this technology gives us the opportunity to prove that's true".

Perhaps this new technology could contribute to the study of sleep patterns in humans in the near future, but for now, the sloth is proven to be less of a "sloth" than all of us first perceived.

To read the original article, refer to:

http://news.bbc.co.uk/2/hi/science/nature/7396356.stm

Posted By: Helen Thi(6) 10/24

Overgrazing leads to increased salamander populations?

That is what a recent study lead by Katherine Greenwald of Ohio State University seems to be suggesting. In her results, overgrazing by high populations of white tailed deer led to an increase in organisms like salamanders, snakes and other invertebrates. In the past, the increasing numbers in the deer population have led researchers to believe to have affected the bird inhabitants and the amount of flora present in that area.

With more forest areas become smaller over the past few decades predators like wolves and cougars are not around leading to dramatic increase in white-tailed deer in the eastern US and allowing them to graze freely at forest edges where they typically roam. Greenwald’s findings were definitely unexpected as stated by University of Turku’s Otso Suominen, who assumed that the high populations of deer would only be beneficial for organisms such as snails and slugs.

One theory explaining their findings is that the areas in which there are a high population of deer also means there will be more of their droppings present in the soil which then leads to higher soil quality. With the increased nutrients present in the soil more invertebrates become attracted to the area which also attracts salamanders because of the increased abundance of their food source inhabiting the area.

Because the study is only in its early stages Greenwald is hesitant to state that the high density of deer has any direct influence on the increased populations of salamanders, snakes and other invertebrates. With further research by Greenwald and others hopefully more information will shine a new light on their findings.

http://www.msnbc.msn.com/id/27366401/#storyContinued

Posted by Debbie Theodat(6) 10/24

Updated 10/28:

According to the article, the white-tailed deer’s predators are not usually around to prevent the high populations of deer. Because they are fairly scarce in those areas whatever droppings that are there would not be efficient enough to dramatically affect the soil like white-tail deer have done. The high populations of white-tailed deer present means that there are also far more of their droppings in the soil than that of their predators.

The connection between the overgrazing and the increased populations in the salamanders, snakes and other invertebrates is that the areas where the white-tailed eat are also areas where they leave their dropping. The droppings that are present in the soil improve the quality of the soil by increasing its nutrients. The increased nutrients in the soil become ideal living conditions for insects and other invertebrates. The increased population of their food source present in one area attracts the salamanders who then attract snakes, who are also one of their predators.

Salmons for Grizzly Bears? Wolves love Salmons too.


It is very easy to think that major consumers of tetrapods are either us, humans and grizzly bears. Chris T Darimont, Paul C Paquet, and Thomas E Reimchen from British Columbia recently added one more species, Canis lupus, to the list.

According to the research done by Darimont, Paquet, and Reimchen, Canis lupus, Commonly known as wolves, preferred salmons over deers if the two preys were available at the same time.

The study was done in eight groups of wolves living along the central coastline of British Columbia for three seasons in four year periods. Researchers analyzed contents of wolf feces and hairs. Comparing feces contents to what nutrients are available from which preys, Researchers determined the change in dietary behaviors of the wolves.

From the winter through the summer, 80%~90% of wolves were found to consume deers; however, 40%~70% of wolves hunted salmons during the fall. During the periods of the research, deer availability did not vary from one wolf group to the others. And as one may know already, salmons were available to wolves only in the autumn. Scientists could conclude using these data that salmon eating behavior depends on salmon availability rather than on deer availability.

The researchers suggested that this study may help explaining the cause of declining numbers of salmons.

Research Article from BioMed Central
Spawning salmon disrupt trophic coupling between wolves and
ungulate prey in coastal British Columbia

Posted by: Yi, Jeongsang (6)

Update (10/28):

According to the research done by Darimont, Paquet, and Reimchen, Canis lupus, commonly known as wolves, preferred salmons over deers if the two preys were available at the same time. The wolves live in the central coastline of British Columbia, and hunt deers for the major food source except in the fall.

The researchers suggested the reason for this salmon eating behaviors using the research done by Szepanski et al.; this behavior appeared as availability of deers became lower in shore side rather than in islands. Darimont, Paquet et al. hypothesized the salmon eating behavior depends on availability of the preferred food sources.

Unfortunately, the method of salmon catching is not observed. It is not found out whether wolves eat leftovers from what bears had, or catch in a group. But the researchers suggested that this study may help explaining the cause of declining numbers of salmons observed over years.

Posted by: Yi, Jeongsang (6)

Suicidal Crickets: Manipulated by Worms

Parasites can manipulate host in varies ways, even causing their host to commit suicide. Hairworm (Nematomorpha) are small aquatic worms that start off as parasitic terrestrial tertrapods in their larval state (known as pre-parasitic) then mature and reproduce in aquatic habitats. Larvae hatch from eggs within 20 days, and penetrate and encyst in aquatic organisms. Cysts within aquatic insects are carried to land when the insect metamorphoses into a fly. Arthropod hosts are infected upon eating a fly containing cysts. Arthropods known to be infected with the parasitic worms are crickets, beetles, mantids, and grasshoppers.

A research study done by multiple scientists which you can find here has concluded the change in behavior of infected crickets and the hairworms technique for its survival. The hosts are infected by two ways, erratic behavior (abnormal behavior in unusual habitats) and suicidal behavior. The scientist who studied the infected crickets set up tanks that mimicked the habitat of crickets. In the tanks were large bowls of water. The analysis was based on 173 infected crickets (only carrying one parasite to avoid any bias) and 158 uninfected crickets. 82% of infected cricket’s committed suicide and only 9% of uninfected crickets committed suicide. It was observed that parasites that induced erratic behavior in their host had a much lower fecundity rate (production of eggs) than those parasites that induced suicidal behavior upon their host.

Approximately a week after a host is infected with the suicidal behavior the crickets would look for a water source and simply jump in the water and drown themselves. The parasite needs their host to jump in the water before it matures. Once in the water, the juvenile is able to mature and reproduce in its aquatic environment and repeat its evolved life cycle.

Posted by Carlos A. Varela (Week 6)

Mice and Science: Forgetting the Past

A recent article in Scientific American reveals how scientists from the Medical College of Georgia have managed to erase memories in mice. It has been found that altering the level of an important protein in the brain, known as alpha-CaMKII, can selectively delete certain memories. Alpha-CaMKII is a protein that contributes to learning and memory development. Scientists manipulated the activity of this protein in mice to influence how well short and long term memories can be stored. Mice that were conditioned to recall stimuli such as an electric shock at the same time that the protein was turned up in their brain seemed to forget the memory of the shock while not forgetting anything else. It has been suggested by some experts that it could be beneficial to erase certain memories in humans, such as those suffering from trauma. However, Joe Tsien of the Medical College of Georgia, warns of such procedures: "All memories, including the painful emotional memories, have their purposes. We learn great lessons from those memories or experiences so we can avoid making the same kinds of mistakes again, and help us to adapt down the road". Whether or not such a procedure could ever be performed on a human is one question, but perhaps a more important one is whether it should be.

Posted by: Benjamin Spozio (6)

Update (10/27/08): It was nice to see so many comments on this article that related to the moral implications of such a controversial subject. I firmly agree with all those who commented on the dangers of erasing memories. As numerous people said, memories certainly serve an important role in our day-to-day decision-making and social interactions. The potentially negative consequences of tampering with such a personal aspect of our being must certainly be taken into account before testing could be done on a human subject. However, I was quite interested to read a comment that suggested using a corollary of this technology to perhaps help those actually suffering with memory problems, such as Alzheimer's. I had not looked at this scientific development from that aspect, and it made me reconsider whether or not some good could come from this. It was also interesting to see one person mention a scientific parallel to the movie "Eternal Sunshine of the Spotless Mind" because the article itself actually made reference to that exact film (which is worth watching for anyone who has not seen it).

Bonobos' Hippie Reputation Ruined

The primate species commonly known as the bonobo is a peaceful relative to the male-dominated, violent common chimpanzee. Females have a higher social status than males in bonobo society and the troupe sometimes comes together for group sex. bonobos have been observed kissing on the lips and are accused of being the most empathic, sensitive primates. The society of the common chimp is much more violent and male dominance is associated with infighting, hunting and meat consumption which are behaviors virtually absent in bonobos.

According to a new study published in Current Biology, the first direct evidence has been found of bonobos hunting and eating the young of other primate species. This is not expected from a peaceful group of monkeys who use sex to resolve conflict.

Three instances of successful hunts by bonobos in which the primate, of another species, was captured and eaten. The researchers found that both sexes hunt together, and the involvement of females is probably due to their high social status. Alliance formations and hunting seem to be intricately related in ape social life.

"In chimpanzees, male-dominance is associated with physical violence, hunting, and meat consumption. By inference, the lack of male dominance and physical violence is often used to explain the relative absence of hunting and meat eating in bonobos. Our observations suggest that, in contrast to previous assumptions, these behaviors may persist in societies with different social relations." Gottfried Hohmann said, an associate of the Max-Planck-Institute for Evolutionary Anthropology.

This new finding challenges the idea that male dominance and aggression leads to the hunting behavior that we see in chimps. Correlation and causation were confused here. Hunting and male dominance positively correlate, but do not have an absolute causative relationship. Apparently, other social and ecological factors lead to hunting.

Early models of the evolution of aggression and humans used the assumption that male dominance and aggression leads to hunting, but the new discovery casts doubt on this explanation. A female dominated troupe of peaceful apes being observed eating baby monkeys is about the strongest refutation possible.

The study was written about in Science Daily last week. LINK

Jimmy Sullivan (6)

Update

Katie Cole, Erica Damon, Amy Kawazoe, Susan Doung:

The researchers from the study think that this behavior was present the whole time, but unknown to science. I think that this behavior has been around awhile, but is just less common in bonobos than chimps, which is why it was overlooked. It is definitely a left over from when bonobos split from chimps. The ecological factors to answer why it is less common in bonobos is still unknown.

Amanda Joyce, Chantal Gomes, Sarah Moltzen:

The females are more aggressive than the males, and the hunting parties include both sexes. Alliances are the most powerful social tool in chimp world, and in bonobos, the females are the leaders and organizers of them.

Sasha Rogers, Hanbing Guo, Maura Mulvey:

Eating other monkeys is definitely about food for bonobos and chimps. They hunt many different types of animals too.

Kiel Boutelle:

I did a little reading on female dominance in apes. In most ape species, males are dominant. High ranking females frequently outrank low ranking males, and females have been known to gang up and chase a male off. In most prosimian species, females dominate society. There is a lot of research done on the topic, you should check it out.

Ada Marie Flores:

No case studies mentioned.

Amanda Sceusa:

The behavior was observed, and a monkey finger was found in bonobo scat.

So Jin Lee:

Bonobos are probably peaceful and nice when it benefits them and violent when it benefits them. Baby eating seems to contradict their peaceful ways, but a bonobo would probably find humans to be incoherent as well. It is all about the umvelt.

Jurassic Park More Like Jurassic Disco

In the Jurassic period most of the western United States was a Sahara type desert. Most scientists agree that large dinosaurs couldn’t survive in great numbers in this type of environment however, that was soon challenged.

Recently geologists form the University of Utah have found thousands of dinosaur foot prints. They are all clustered in an area of less than an acre. The density and sheer number of tracks makes the researchers refer to this as a dinosaur dance floor. This large concentration leads the scientist to believe that it was a desert oasis and that large numbers gathered here.

A graduate student who discovered the site describes the animals as "happy to be at this place, having wandered up and down many a sand dune, exhausted from the heat and the blowing sand, relieved and happy to come to a place where there was water." While this is slightly colorful description it would makes sense that a desert oasis would gather huge numbers of animals in a dry harsh environment.

Clearly this is an important discovery into dinosaur social behavior which given they have been extinct is very difficult. Also this will prove a site of large scale research.

http://news.yahoo.com/s/ap/20081020/ap_on_sc/sci_dinosaur_dance_floor;_ylt=AhjkjKLYIUehhp5Q7qV6KJ4PLBIF

Matthew Sousa(5)

update:

More recent report shows 40 cm wide upright carnivore tracks. This shows that there is more going on than a herd of animals gathering. Clearly there is a diverse group of animals present. However, there are a number of strange pothole like impressions found and may scientists disagree as to what they are. Also another mystery is why, if this was a gathering place and had carnivore are there no bones. Clearly there are some questions but more research should lead to more answers.

What do Sea otters share with Bald Eagles?

According to Robert Anthony and the Oregon Cooperative Fish & Wildlife Research Unit of the U.S. Geological Survey and Oregon State University they have a lot in common. Since the 1970's scientists have understood that kelp, urchins and otters all play an important role in each other's life cycle. Ur chines are the main predator of sea kelp. They attach themselves to the prey and can defoliate entire kelp forests if their number is great enough. Luckily for the kelp, sea otters enjoy eating these pesky urchins. These otters actually keep the sea urchins in check disabling them from eating all the kelp around. Unfortunately for Alaskan kelp, their savior otters are being driven away by yet another predator, the killer whale. Over the last few decades killer whale populations have increased which effects the otter population in two ways. The first of which the population will decrease because the chance of being preyed on by a killer whale increases. Secondly, the sea otters are forced to move their colonies elsewhere. Both of these effects allow sea urchins populations to grow enabling kelp forests to become defoliated.
This is where the Bald eagle comes into play. Alaskan bald Eagles set up nests on cliffs right on the shore. 90% of their diet comes from the ocean (usually relatively small fish). kelp forests usually provide a shelter and food source for these fish. When the otters are forced away and the urchins are given the power, these fish suddenly find themselves migrating to the next closest kelp forests. These bald eagles now have to find alternative sources of food which usually turns out to be other marine inhabiting birds. This shift in their diet not only effects the way eagles are forced to prey but also effects related populations of species.
The sea otter has long been known to be a keystone species in the ocean. Because of its detrimental protection of the kelp forests it plays a large role in determining the behaviors of other species. This study however, is the first time that the presence of the sea otter has been shown to have an effect on a terrestrial species.

Patrick Salome

Infant Not Sleeping?

Harvard medical school has revealed that maternal depression, breastfeeding, a lower socioeconomic status are all associated with a decline in infant sleep in the first six months of life. The study was preformed by Michael Nevarez. He focused on 1,676 mother-infant pairs. According to his results an infants mean sleep duration is 12.2 hours. It is recommended that infants get 14-15 hours of sleep her day.

I think that breastfed babies are sleeping less because breast milk is digested much faster than formula. On average a breast fed baby will nurse every 1 1/2 to 2 hours throughout the day. Whereas a bottle bed baby will average every 3 to 4 hours. This means that breastfed babies are constantly being woken up because their bellies are hungry and they need to be awake to nurse.

http://www.sciencedaily.com/releases/2008/06/080609071243.htm

Update:

Infant Not Sleeping?

Harvard medical school has revealed that maternal depression, breastfeeding, and a lower socioeconomic status are all associated with a decline in infant sleep in the first six months of life. The study was preformed by Michael Nevarez. He focused on 1,676 mother-infant pairs. According to his results an infants mean sleep duration is 12.2 hours. It is recommended that infants get 14-15 hours of sleep per day.

The socioeconomic status of a mother can indirectly affect an infants sleep duration. If a mother comes from a lower socioeconomic status she may not be able to afford proper nutrition to provide adequate breast milk for her baby. This will result in the infant awaken more frequently because they are still hungry since they're not receiving enough vitamins and minerals through the breast milk.

http://www.sciencedaily.com/releases/2008/06/080609071243.htm

Jennifer Smith (5)

Scientists at the University of Washington in Seattle, Washington, recently tested a device that might help with certain nerve damage. They tested the devices on monkeys which had paralyzed muscles. They found that the monkeys were able to regain movement by learning to control a single brain cell. "The device monitored the activity of a brain cell and used that as a cue to stimulate wrist muscles electrically. Researchers found it could even use brain cells that normally had nothing to do with wrist movement." Chet Moritz said in the article. In the experiment two macaques at different times and learned that using their wrists to move a cursor on a computer screen. This research might have a significant effect in the future with paralyzed limbs it might lead to the possible elimination of the problem all together.

http://www.cnn.com/2008/TECH/science/10/15/bypassing.paralysis.ap/index.html


Charles Scondras

Birds and Beavers, One Happy Family??

Although it may seem like an unusual combination, recently, researchers found that beavers actually help create an important habitat for a plethora of migratory songbirds. This study, published in the journal Western North American Naturalist found that the diversity and number of local songbirds increased when a beaver dam was built.

In the Western American Regions, the number of Beaver populations has dramatically decreased because of the fur trade ever since the 1800’s. Hilary Cooke, the author of the study said, "this habitat is critical to birds in semi-arid regions yet has been severely degraded or lost through much of the West. Our results suggest that management of beavers may be an important tool for restoring habitat and reversing bird declines." Other than being hunted, Beavers are also considered pests because they are known to cut down trees. Also, they are known to flood property, which explains why they aren’t seen as the most peaceful of animals.

Steve Zack, a co-author of the Wildlife Conservation Society said, “Beavers help repair degraded stream habitats and their dams and associated ponds recharge local water tables and create wetlands. With our changing climate likely to mean increasing droughts in the West, managing ways to allow watersheds to act more like sponges will be a challenge. Beaver are a powerful tool to be considered for that, and the associated benefits to other wildlife add to their value." It truly is incredible that it is due to these collections of water created by Beavers that allow songbirds to become more abundant.

The full article can be found here

Ahmed Sandakli (5)

Update:

Thanks All for the insightful comments and questions. There were many important points brought up that I would like to look into. The abundant songbird diversity in beaver’s dams is due to the fact that in these ponds made through dam building; there are many kinds of vegetation that are able to grow.

One question was raised asking if the beavers supplied the birds with branches that they used to make their nests, and the answer to that question is no they don’t. Its simply because of the source of food present due to the environment created by the dams that the beavers build.

Another comment asked why beaver populations aren’t on the rise, since regulations and laws exist to protect animals. The reason for this is that to this day, beavers are considered a pest because they take down trees and flood properties of people.

Ahmed Sandakli