James Lovelock came up with a hypothesis that he named Gaia, which means The Goddess of the Earth, in Greek. This hypothesis claims that the Earth evolves, making it more livable, by doing things like controlling the climate, the elements in the atmosphere, and even the salt concentrations in the ocean.
Climate control is very important in order for life on Earth to survive. As each day passes, the sun becomes more and more hot. Lovelock claims that the Earth balances out this heat by doing things like creating more greenhouse gases, like carbon dioxide and methane gas. Methane gas can be produced a number of ways, but a very efficient technique is found in termites. Termites can be found in over two thirds of the Earth's surface. Termites eat wood and convert it into the methane gas when it is digested. Termites are the second largest source for the production of methane gas.
Lovelock also claims that the Earth controls the amount of oxygen that is produced at 21 percent. This is crucial because have too much oxygen would mean that forest fires would burn for much longer than now. Having below fifteen percent would mean that fire couldn't be sustained.
Many people don't agree with Lovelock and his hypothesis, but I believe that more and more people are coming around to it.
Thursday, January 27, 2011
Tuesday, September 28, 2010
Amber Kapchinske "attack frequency based on prey group size"
Attack frequency, attack success and choice of prey group size for two predators with contrasting hunting strategies
The size of a flock of redshanks affected the method of hunting used by two species of raptors. Predators have various modes of hunting that are determined by the response of the prey. Sometimes it is more appropriate for the prey to be chased down before it is captured or killed. Other times it is more appropriate for the prey to be caught by surprise. In this study the size of the redshank flock determines which method the raptors will use in order to obtain the most successful attacks.
If the flock size of redshanks increased, the attack success of peregrines declined when using the surprise –attack and the nonsurprise-attack. The sparrowhawks attack success declined when using the surprise-attack only. The sparrowhawks attack success did not decline when it used non-surprise attacks because it only used this mode of predation when it was already spotted by the redshank. The Peregrine falcon and the sparrowhawk varied in hunting style only when a flock of redshanks was large. The sparrowhawk hunted mostly from cover and the Peregrine falcon preferred to attack from the open where the prey could see him. When the prey lived in a smaller flock, they relied on vigelence to protect against predators. When the redshanks lived in a larger flock, they relied more on the confusion effect.
When the surprise attack mode of predation was used, the success of attacks involving both species of raptor decreased as the population of the prey increased. This leads us to the conclusion that having a greater number of redshanks in a flock will ensure the highest rate of survival for the flock.
Check out this video of a peregrine falcon attacking a grouse!
http://www.arkive.org/peregrine-falcon/falco-peregrinus/video-08c.html
Wednesday, April 28, 2010
Chimps can Mourn!
Through several data stating that chimpanzees and humans are 97%, 98%, or 99% similar DNA wise mean one thing: chimpanzees are very closely related to humans. It can be easily observed that our body structure, intellect, and especially behavior and those of chimpanzees display some commonalities. With these in mind, do chimpanzees feel any emotional attachment to others? In a recent article, two experiments were initiated to observe how chimps respond to the death of those close to them.
Chimpanzees actually respond to dying chimps as well as dead chimps. This shows how highly developed their awareness of death in contrast to what has been suggested before. Researchers believe that this aspect is involved in their sense of self awareness much like their being able to self-recognize and displays of empathy for others.
A major difference between how humans react to the death of a close one and how the chimp reacts is truly different. Chimps tend to be more calm compared to humans be frenzied and becoming traumatized.
In the first study, the researchers were able to observe how much attention is paid to a dying adult female chimp. Before the chimp died, those around her groomed her as well as caressed her. By caressing her, the other chimps are testing for any signs of life or death. Right after she dies, the other chimps left her while her daughter stuck beside her mother throughout the night. For many days, the chimpanzees avoided going near the dead chimp’s sleeping spot.
In a different study, five members of semi-isolated chimp community were witnessed dead. Of the five, two were infants. The response from the mother chimps to her child’s death was to carry it on her back for weeks and months following their death. They also treat the dead as though they were alive such as carrying them everywhere, grooming them, and taking them into the nests during the day and night. As days pass, the mothers are able to let go little by little, allowing others to handle the dead.
This exemplifies how highly aware chimpanzees are concerning death. Also, this displays how strong the bonds are between mother and infant chimps. It’s truly amazing how readers are able to understand somewhat how the mother chimp feels or how an infant chimp feels about the death of the other. What truly surprised me was the fact that in spite of the dead infant chimp, the mother would allow other infants to play with the dead corpse as though it was normal. That’s going to an extreme.
Posted by Vinh Tran
Chimpanzees actually respond to dying chimps as well as dead chimps. This shows how highly developed their awareness of death in contrast to what has been suggested before. Researchers believe that this aspect is involved in their sense of self awareness much like their being able to self-recognize and displays of empathy for others.
A major difference between how humans react to the death of a close one and how the chimp reacts is truly different. Chimps tend to be more calm compared to humans be frenzied and becoming traumatized.
In the first study, the researchers were able to observe how much attention is paid to a dying adult female chimp. Before the chimp died, those around her groomed her as well as caressed her. By caressing her, the other chimps are testing for any signs of life or death. Right after she dies, the other chimps left her while her daughter stuck beside her mother throughout the night. For many days, the chimpanzees avoided going near the dead chimp’s sleeping spot.
In a different study, five members of semi-isolated chimp community were witnessed dead. Of the five, two were infants. The response from the mother chimps to her child’s death was to carry it on her back for weeks and months following their death. They also treat the dead as though they were alive such as carrying them everywhere, grooming them, and taking them into the nests during the day and night. As days pass, the mothers are able to let go little by little, allowing others to handle the dead.
This exemplifies how highly aware chimpanzees are concerning death. Also, this displays how strong the bonds are between mother and infant chimps. It’s truly amazing how readers are able to understand somewhat how the mother chimp feels or how an infant chimp feels about the death of the other. What truly surprised me was the fact that in spite of the dead infant chimp, the mother would allow other infants to play with the dead corpse as though it was normal. That’s going to an extreme.
Posted by Vinh Tran
Sunday, April 25, 2010
Male Combat Favors Female Biased Populations in Species
A group of herpetologists from Indiana University’s Biology Department, Steven Freedberg and Michael Wade, decided to combine several theories of environmental sex determination, and female gender selection to provide a more inclusive theory on reptilian sex determination. There was no actual experiment done to test their hypothesis, but the evidence and proven background theories provide a realistic commentary within their proposal.
Male vs. Male combat is present in many species throughout the animal world. However it is more rare in cold-blooded animals. Both the snapping turtles and in many crocodilians this male combat has shown determine male territories and establish a social hierarchy throughout the population. In snapping turtles males often have a significant amount of scars and missing claws when compared with females, which are indicative of a male cost to reproduction. As many of you know, the males at the top of the hierarchy achieve more access to mates and therefore have a higher reproductive success rate. This means that a male’s adult morphology plays a much larger role in how successful they are in passing their genes on to the next generation.
On the other side of the spectrum are the females. Crocodilian females typically live and breed in a male’s territory that he has established through fighting. A number of females can live within one male’s territory and all mate with the male who supplies the environment for them.
One theory that plays a role in sex determination in crocodilians is ESD or Environmental sex determination. This theory is relatively self-explanatory. It simply means that sex is determined through environmental cues such as temperature. This theory yields the hypothesis that an equilibrium sex ration is not 1:1, but rather favors the gender that is produced more frequently in poorer environments
Another theory that actually calculates which sex should be produced in these particular environments is the Trivers-Willard Hypotheses, which states that mothers produce females in poorer environments (particularly in species with male combativeness). In reptilians, temperature does play a role in gender identification, however there is no temperature pattern that coincides with gender determination across all species of reptilians.
A last theory that contributes to this overall picture is Shuster-Wade’s sexual dimorphism theory. In species where there is male combativeness there seems to be two outstanding male attributes. The first being that males have a selective pressure on size represented in their disparity in size when compared with females of the same species and secondly in their forced insemination patterns.
Freedberg and Wade are conveying a summary of these theories that pertains to species of Herps that display male combativeness. Their theory states that females are more common within these species because it is more fitness effective. Males have a larger selective pressure (competitive combat) in their adult stages to be successful breeders than females do. Therefore mothers will produce more females in poorer environments (which are more common in nature) and more males in richer environments to achieve their own reproductive success. These species achieve this gender determination by through environmental cues specific to their species. (ESD)
A group of herpetologists from Indiana University’s Biology Department, Steven Freedberg and Michael Wade, decided to combine several theories of environmental sex determination, and female gender selection to provide a more inclusive theory on reptilian sex determination. There was no actual experiment done to test their hypothesis, but the evidence and proven background theories provide a realistic commentary within their proposal.
Male vs. Male combat is present in many species throughout the animal world. However it is more rare in cold-blooded animals. Both the snapping turtles and in many crocodilians this male combat has shown determine male territories and establish a social hierarchy throughout the population. In snapping turtles males often have a significant amount of scars and missing claws when compared with females, which are indicative of a male cost to reproduction. As many of you know, the males at the top of the hierarchy achieve more access to mates and therefore have a higher reproductive success rate. This means that a male’s adult morphology plays a much larger role in how successful they are in passing their genes on to the next generation.
On the other side of the spectrum are the females. Crocodilian females typically live and breed in a male’s territory that he has established through fighting. A number of females can live within one male’s territory and all mate with the male who supplies the environment for them.
One theory that plays a role in sex determination in crocodilians is ESD or Environmental sex determination. This theory is relatively self-explanatory. It simply means that sex is determined through environmental cues such as temperature. This theory yields the hypothesis that an equilibrium sex ration is not 1:1, but rather favors the gender that is produced more frequently in poorer environments
Another theory that actually calculates which sex should be produced in these particular environments is the Trivers-Willard Hypotheses, which states that mothers produce females in poorer environments (particularly in species with male combativeness). In reptilians, temperature does play a role in gender identification, however there is no temperature pattern that coincides with gender determination across all species of reptilians.
A last theory that contributes to this overall picture is Shuster-Wade’s sexual dimorphism theory. In species where there is male combativeness there seems to be two outstanding male attributes. The first being that males have a selective pressure on size represented in their disparity in size when compared with females of the same species and secondly in their forced insemination patterns.
Freedberg and Wade are conveying a summary of these theories that pertains to species of Herps that display male combativeness. Their theory states that females are more common within these species because it is more fitness effective. Males have a larger selective pressure (competitive combat) in their adult stages to be successful breeders than females do. Therefore mothers will produce more females in poorer environments (which are more common in nature) and more males in richer environments to achieve their own reproductive success. These species achieve this gender determination by through environmental cues specific to their species. (ESD)
Friday, April 23, 2010
Promoting Health Through Coffee
Coffee is one of the most demanded drinks by people. People drink coffee to get up in the morning and to stay awake during the day. It seems like everyone is drinking coffee. For me, however, coffee isn’t such a big deal. I never drink it and feel that I would rather go without it because I like my body to naturally wake up on its own without the aid of some outside substance such as coffee. Although I assumed coffee as only helping a person wake up, it seems like coffee has other effects.
According to an article on science daily, coffee can help many different aspects of a person’s health. From the article, it seems like coffee can help lower chronic inflammation and raise our good cholesterol. It also contains nutrients such as calcium and other compounds that may promote health. Coffee’s role in helping to reduce type 2 diabetes was also mentioned in this article and, for me, was the most interesting and surprising.
Although I am still hesitant to drink coffee because I don’t want to become reliant on it, it seems like coffee would be good to drink for other reasons other than trying to become more awake in the morning and throughout the day. Because this article does not talk much about coffee’s role in helping to prevent type 2 diabetes, I would like to look at other sources to see more about this.
Posted by Kayla Perry
According to an article on science daily, coffee can help many different aspects of a person’s health. From the article, it seems like coffee can help lower chronic inflammation and raise our good cholesterol. It also contains nutrients such as calcium and other compounds that may promote health. Coffee’s role in helping to reduce type 2 diabetes was also mentioned in this article and, for me, was the most interesting and surprising.
Although I am still hesitant to drink coffee because I don’t want to become reliant on it, it seems like coffee would be good to drink for other reasons other than trying to become more awake in the morning and throughout the day. Because this article does not talk much about coffee’s role in helping to prevent type 2 diabetes, I would like to look at other sources to see more about this.
Posted by Kayla Perry
Thursday, April 22, 2010
Male monkeys use babies to make guy friends
It seems like a good plan. Whether it’s a cute baby or dog a cute defenseless being somehow allows one to better socialize with other. It’s the same for some monkeys as well, but I thought the benefit would be only meeting more females. Turns out I’m wrong.
A new study published in Animal Behavior has found that male Barbary macaques have a better chance of bonding when one is carrying an infant on their back. When the two males meet they undergo a ritual of sorts. Julia Fischer, one of the authors describes it, "[they] sit together, embrace each other, then they hold up the infant and nuzzle it. Their teeth chatter and lip smack while making low frequency grumbling noises."
There are significant benefits to having a bunch of guys as friends as well. One monkey rose from fifth to second place on the social ladder by having the most male friends. The baby also doesn’t even have to belong to male carrying it.
However the research also found a cost to using your baby as a “social tool.” Feces samples taken from males, who carry their babies, showed that they had higher stress levels. Baby macaques sound very similar to human infants when they cry, so its not surprising that the male gets stressed out when this happens.
Social benefits are known to occur for females holding a baby as well (more grooming and attention). Although, I was surprised to learn that the same thing occurred with males getting popular with the other men in the group and rising in rank. Yet another interesting behavior displayed by monkeys.
Posted by Daniel Solomon (3)
Wednesday, April 21, 2010
Could Excessive Friday Night Drinking Lead to Cancer?
Typically college students spend their weekends partying. This social environment can lead to excessive drinking and alcohol consumption problems. We've heard that too much drinking can affect your liver and kidneys but today was the first time I heard it can affect the structure of your telomeres. What is the big concern? Well, your telomeres are important to the genetic stability of your cells. The telomeres are already shortening as age progresses due to the natural processes of the body which makes the genetic information in the cells less stable normally. Recent research has shown that excessive alcohol consumption could increase the progression of these telomeres shortening more rapidly that normal. This idea makes you wonder if the telomeres shortening is what makes heavy drinkers typically appear older than they really are. When cells are less stable due to telomeres shortening there is a greater risk of genetic mutations, which is the main cause of many cancer types.
In a recent article, " Excessive Alcohol Consumption May Lead to Increased Cancer Risk" the author describes current research lead by Andrea Baccarelli, M.D, Ph. D. who is the head of the Center of Molecular and Genetic Epidemiology , Ca' Granda Hospital Foundation at the University of Milan, Italy. Baccarelli currently is involved in research testing the relation of excessive drinking to shortening of telomeres. She preformed Polymerase Chain Reaction testing or PCR on all of her participants. This group was divided into people who abused alcohol and people who have variable alcohol consumption. To eliminate many variables this group were all similar in age, environment, diet, and other factors related to their everyday life. After testing results showed that the length of the telomeres where dramatically shorter in those participants who were excessive drinkers.
I was interested to see the results of this study. You always here of smoking being a lead cause in some cancer types and now excessive alcohol drinking is coming more serious in other ways the alcoholism. This article isn't saying that having one drink is going to cause your telomeres to dramatically shorten and cause a genetic mutation. This article is more of a warning that alcoholism can pose as a greater risk to health than we may have thought. So think twice before you drink that whole bottle of vodka next weekend it may not be worth it.
Article: http://www.sciencedaily.com/releases/2010/04/100421102336.htm
By Valerie Silva
In a recent article, " Excessive Alcohol Consumption May Lead to Increased Cancer Risk" the author describes current research lead by Andrea Baccarelli, M.D, Ph. D. who is the head of the Center of Molecular and Genetic Epidemiology , Ca' Granda Hospital Foundation at the University of Milan, Italy. Baccarelli currently is involved in research testing the relation of excessive drinking to shortening of telomeres. She preformed Polymerase Chain Reaction testing or PCR on all of her participants. This group was divided into people who abused alcohol and people who have variable alcohol consumption. To eliminate many variables this group were all similar in age, environment, diet, and other factors related to their everyday life. After testing results showed that the length of the telomeres where dramatically shorter in those participants who were excessive drinkers.
I was interested to see the results of this study. You always here of smoking being a lead cause in some cancer types and now excessive alcohol drinking is coming more serious in other ways the alcoholism. This article isn't saying that having one drink is going to cause your telomeres to dramatically shorten and cause a genetic mutation. This article is more of a warning that alcoholism can pose as a greater risk to health than we may have thought. So think twice before you drink that whole bottle of vodka next weekend it may not be worth it.
Article: http://www.sciencedaily.com/releases/2010/04/100421102336.htm
By Valerie Silva
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