Wednesday, November 30, 2011

Monkeys Mother Wingmen

How often do you find your mother setting you up with a date? For a young male muriqui monkey of Brazil, his mother is the best wingman he could hope for. Troops of muriquis are led and run by a matriarch. This older female can live upwards of thirty years, and governs the mating that happens within her troop. Because of this, there is no competition for male dominance in mating. Instead, the matriarch's policy seems to be "everyone gets a share." Although some males are preferred and will have greater reproductive success, all the males will get the chance to pass their genes along. This raises the question: "if everyone has a chance to pass on their genes, doesn't that take natural selection out of the picture?" If the males are not competing or being selected for, then detrimental traits could be passed along, harming the overall population. This species is severely endangered, so this could be part of the reason.


Posted by Rhys Ursuliak (9)

"High Five!" Cried the Raven


RAVENS use "HAND" GESTURES to COMMUNICATE

If I asked you what a wing was for, chances are you would tell me it helped birds fly. Would you ever think that a wing, which has the same basic anatomical bone structure of the hand that any animal with an actual hand has, could use its wing to make gestures, as well? A recent study has shown that ravens use their beaks and wings similar to the way humans use their hands, and can perform gestures such as pointing to objects. Until now, this behavior has not been seen by scientists in anything other than primates. Although dogs have been observed to point to things, they were excluded as a possibility, since they are taught this action by humans. Even when considering primates, gestures comparable to those of humans are rarely seen. One instance where such a gesture has been seen is in Uganda, where chimpanzees use directed scratches to point out parts of their body they would like groomed.

With more and more research, ravens have been found to be extremely intelligent creatures, out-competing with apes in some cases. Biologists have found them to be a very object- oriented species.

Research involving ravens has shown that they use their beaks to motion to and offer items, like moss, stones and twigs, which often leads the gestured to look at the object. Those gestured are commonly members of the opposite sex. The two would then interact directly, maybe by clasping their bills together or jointly manipulating the item. This has suggested that these gestures are used to measure interest of a partner or to reinforce bond strength. This has completely blown the expectation of what a "gesturer" should look like, considering that the raven has wings instead of hands, a beak and is able to fly, yet can still take advantage of nonvocal communication in this way.

It is a fact that ravens possess a high level of cooperation between partners, which suggests that gestures evolve in species that demonstrate a high degree of collaborative abilities. This discovery could open new possibilities on the origin of gestures within humans. One thing is certain, further research must be done on the other various gestures of ravens in order to make connections between function and meaning that could shed light on our own species' development.

http://www.livescience.com/17213-ravens-gestures-animal-communication.html

Posted by Chelsea Van Thof (9).

Platypus Electroreception


What do you call a cat-sized, venomous, egg-laying semi-aquatic mammal with the bills of a duck, the tail of a beaver, and the feet of otters? When European naturalists first encountered the platypus, they thought that it was an elaborate conspiracy against science. All oddities aside, platypuses are ones of the only mammals that are able to use electroreception (the only other one is the echidna, or spiny anteater). The platypus has the most sensitive sense of electroreception out of all the mammals, and the receptors are located in their bills. They swim in a characteristic side-to-side motion because they are able to determine the direction of any electrical source (this, of course, works better in water). Electroreceptors in the bill are coupled with mechanoreceptors to perceive both electric signals and tactile ones. Tiny pressure pulses are detected by the bill, which direct the platypus to its prey. To feed, the platypus will dive to the bottom of the stream and dig with its bill. When tiny electrical signals are detected by the muscular contractions of organisms are detected, it will then close in on its prey. Experiments with robot shrimps sending out electrical signals have also triggered this response. These mammals are unique in that it feed by neither sight nor smell. They also possess spurs in their hind legs that inject a venom causing tremendous pain to mammals as big as humans. They also store food in their cheeks while preying, similar to squirrels. These mammals make centaurs and unicorns look normal.

http://www.animalcorner.co.uk/venanimals/ven_mammalsPlat.html

Posted by Michael Shi

Lyre Birds

http://www.cracked.com/article_19483_5-birds-with-abilities-that-put-superheroes-to-shame.html

So I know the link I have above isn't the most scientific reference , but this bird is quite fascinating. The Lyre bird is able to mimic any sound it hears. This is truly remarkable considering we went through examples a couple weeks ago where if a bird does not hear the correct song, the song can get distorted. The lyre bird's main song is a mixture of seven elements of its own song and any number of other mimicked songs and noises. They are able to mimic other animals as well such as koalas and dingos. The lyre bird's have the most complex syrinx compared to other songbirds. This allows for it to have unmatched mimicry. Lyre Birds will hear any noise and incorporate those notes into their songs.
The question then remains , how is it that the lyres are able to process all these notes and still be able to recognize their own species calls. Since each lyre may hear different things, each song must be very unique from each other.

Posted by Jobin

Tuesday, November 29, 2011

Poison frogs color evolution

Individuals of the same species, poison dart frogs, can vary greatly as far as color patterns go. Color patterns seen in a population depend on where the frog lives.

Researchers from the University of Montreal performed a study in Peru using decoy frogs. They placed 3,600 clay frogs painted three different colors in different spots.

"In the highlands of the Cainarachi Valley there, the frogs are splashed with a green undulating pattern, almost like an abstract snakeskin pattern. In the lowlands only 6 miles (10 kilometers) away, the same species of frog boasts yellow stripes instead."

Frogs that had been painted to look like locals were much less likely to be attacked by predators, because the predators know frogs marked like that are poisonous. Frogs of the same species with different color patterns were twice as likely to become prey. Because the local frogs are known to be poisonous they are not chosen as prey and and much more likely to reproduce, spreading their color pattern.

The fact that color patterns varied so much in populations so close together I found particularly interesting. Also, the rate at which the predators learned that the decoy frogs do not make a good meal was also very surprising, as most of the attacks on the decoys had happened within a day of them being placed.

Wednesday, November 23, 2011

SEX WITH A BEER BOTTLE?



Beetles are dying while trying to get it on with discarded brown beer bottles, according to research conducted by Darryl Gwynne, a University of Toronto Mississauga professor.

It's a case of mistaken attraction, because the beer bottles happen to possess all of the features that drive male Australian "jewel beetles" wild. They're big and orangey brown in color, with a slightly dimpled surface near the bottom (designed to prevent the bottle from slipping out of one's grasp) that reflects light in much the same way as female wing covers. As a result, the beer bottles are irresistible to the male insects, which will die trying to mate with them in the hot Australian sun.

The bottles resemble a "super female" jewel beetle. Male beetles are so captivated by the bottles that they will gird their loins and go through the expected motions, refusing to leave until they fry to death, are consumed by hungry ants, or are physically removed by researchers.

The male beetles are very particular about the bottles. Beer cans or wine bottles do nothing for them. It's all about the shape, color and texture and has nothing to do with booze. As the researchers wrote in their findings, "Not only do western Australians never dispose of a beer bottle with beer still in it, but many of the bottles had sand and detritus accumulated over many months."

While the researchers obviously see the humor in all of this, there's a serious message too. The findings demonstrate how our garbage not only litters landscapes but can also directly affect the populations of other species. This also points out that the research supports a theory of sexual selection: that males of certain species, in their eagerness to mate, are often the ones making mating mistakes.

http://news.yahoo.com/why-beetles-sex-beer-bottles-q-scientists-200203561.html

Posted by Whitney Huynh (8)


Spiders give gifts and fake death for sex!

As we’ve started talking about sexual selection in class, I find it fitting that this week’s blog be about that very subject. In class, we mentioned how the male scorpion fly presents ‘gifts’ to the female, usually a dead bug, in order to distract her so the male can copulate for an extended period of time. Well, as it turns out, these flies aren’t the only one paying for sex. Pisaura mirabilis, also known as the nursery web spider, is European species who also present ‘gifts’ to females in order to distract them so they can copulate. While most males present fresh prey wrapped in silk, some just wrap shell husks in silk and present. Scientists believe the stress of finding a mate forces these males to present anything in order to have a longer copulation time. Researchers from Aarhus University in Denmark and the Instituto de Investigaciones Bioloìgicas Clemente Estable in Uruguay took 20 spiders and set them in groups and gave them gifts to wrap: either no gift, a shell husk, a fresh fly, or a protein-enriched fly. They found the males would wrap the present with silk until it was unidentifiable, giving them more time for copulation as the females would inspect the gift. As expected, males who presented gifts had greater success mating, and those with edible gifts got to mate for a longer period of time. What separates these spiders from other gift-giving species is the other trick they use to mate. If they haven’t copulated for a long enough time, some males will pretend to die, with their gift in hand. The females would then drag the male ‘carcass’ along in order to try to take the gift. Once they stop dragging, the males will revive and mate with the females for a second time (talk about desperate). This feigning death is called thanatosis. And we think human men can pull some weird crap when trying to get a girl.

Picture of male spider giving gift:


Information came from the article “8-Legged Sex Trick? Spiders Give Worthless Gifts, Play Dead” written by Jennifer Welsh on Nov. 13, 2011 from livescience.com. Link:
http://www.livescience.com/17010-spider-gifts-play-dead-mating.html

Posted by Austin Gray (8)

RIP Western Black Rhino


The International Union for Conservation of Nature, otherwise known as IUCN, is an organization that is responsible for collecting the data on endangered species throughout the world. IUCN uses a classifying system to rate the status of a species. This system has ratings such as Least Concern, Near Threatened, Vulnerable, Endangered, Critically Endangered, Extinct in the Wild, and Extinct. Using certain criteria, the IUCN is able to assess populations of different species and determine whether they are in need of protection or not.

Unfortunately, while the IUCN does its best to save species that are teetering on the brink of extinction, it is not always possible. This was the case of the Western Black Rhino, which was just recently declared as officially extinct. Two of it's relatives, the black and white rhinos, are also critcally endangered, and it is thought that they could be gone within the next couple of years.

Rhinos are killed at a rate of about one a day in South African game parks. The WWF estimates around 340 have been slaughtered this year alone. One of the reasons that rhinos are so sought after is because of their horns. The horns can be sold as trophies or can be ground up and used as medicine. Chinese medicine takes these powdered horns and adds them to food or tea as an aphrodistiac.

Rhinos are not the only ones experiencing poaching for medicinal purposes. Tigers, bears, elks and sharks are also thought to have special properties, which has led to the killing of many members of these species as well. The IUCN has declared that around 25% of mammals are at risk of extinction. What these animals need are protection from hunters that can only be given if the demand for their products ceases. It is difficult, maybe impossible to change the beliefs of certain cultures, but it may be the only way to protect certain wild species on this planet.

Posted by Janelle Hayes


The Usefulness of Sea Cucumbers

A lot of humans’ problems have natural solutions. For example, the discovery of penicillin in fungi helped saved millions of lives. Scientists have found use of an organism that may be able to help clean up our oceans - the organism being a sea cucumber. These harmless creatures have a variety of uses, including being a nutritious delicacy in some cultures. Unfortunately, these creatures have been overharvested and sea cucumber populations in the wild are seriously depleted. Luckily, scientists found that sea cucumbers show a great deal of potential in their ability to clean up pollution on the ocean floor. Essentially, scientists plan to use sea cucumbers to clean up the waste created by fish farms.

Humans have left a huge eco-footprint on Earth the past few centuries and we are reaching our limit on how much more damage we can do to the environment. Thus, the discovery of the sea cucumber’s ability to convert the wastes created by fish farms to nutrients for its own survival is a great one. This is a win-win situation, where fish farms are going to be more sustainable with the use of these sea cucumbers and then sea cucumbers would also be saved from extinction. This discovery exemplifies the importance of preserving and studying organisms. We are discovering new species every day and by all of studying them, perhaps we will find solutions to other problems in the world.

Source: http://www.sciencedaily.com/releases/2011/02/110202202952.htm

Posted by James Lin (8)

The "Bloop"





Behold the "bloop". This is a spectrogram of an unidentified sound picked up by U.S undersea microphones in 1997. These hydrophones were placed in oceans all over the world to monitor Soviet submarine movement during the Cold War. The microphone stations lie hundreds of yards below the surface, at a depth where sound waves become trapped in a area known as the "deep sound channel". This layer of water has the perfect combination of temperature and pressure to cause any sound waves to keep going without being scattered by the ocean bottom or the surface. Most of the sounds detected are known to come from whales, ships or underwater earthquakes. Scientists have gotten so good at recognizing these sounds that they can pinpoint the species, and if it has been heard before, even the individual whale. This is why it is so interesting that scientists cannot figure out what exactly made this noise.



This same type of sound was heard several times of the course of the summer of 1997, but never heard again. This sound was heard by two hydrophones 3000 miles apart so it had to be an incredibly loud noise. Most of the time, scientists can tell when these noises come from underwater currents, volcanos or earthquakes, but this was very different.While it displays the varying frequency that is true of most marine animals, it is far more powerful than the calls made by any creature known on Earth. The frequency of the sound meant that it had to be much louder than any animal noise that we have ever heard, including those produced by the largest whales, which are known for creating the loudest noises by any animal on land or in the ocean. The one thing most researchers agree on however, is that it is very likely that it was a living creature.



One theory out there now is that it could have been created by a giant squid. The largest squid ever examined was dead and washed up on shore, only measuring 60 feet. However, there have been countless stories and legends about collossal squid over one hundred feet in length, attacking ships and wrestling with blue whales. One hole in this idea is that squid do not have a gas filled sac that is normally needed to produce these kind of sounds.


If it can't possibly be a giant squid and is much too loud to be a supersized whale, then what is it? 95 percent of uncharted ocean tells me that it is something that we have never seen before.


Decide for yourself






Posted by naina

Tuesday, November 22, 2011

Answer one question, two more arise

New discoveries are always being made in the field of science. New discoveries lead to new theories and hypothesis or reaffirm old theories. The new leads that are always being discovered in science rebuttal old controversies and create new controversies within the field. One current discovery gives more evidence for the theory of evolution.
A whale fossil that is approximately 49 million years old was recently found in the antarctic peninsula. This discovery is creating reform amongst the timeline of whales from quadrupeds to aquatic creatures.It is now believed that the whales evolved into their aquatic form much quicker than previously believed.
The discovery also leads to a discovery of other animals that where around during that period that the whale fed on. Bones of large spiny fish were found along with the whale's jaw bone. New innovations are always found in the field of science that create new questions as well as answering old questions.

Posted by Noelle Kellicker
http://news.nationalgeographic.com/news/2011/11/111116-antarctica-whales-oldest-evolution-animals-science/

Friday, November 18, 2011

Anglerfish

Anglerfish

The Anglerfish is an extremely difficult specimen to study because they are inhabitants of such deep water where there is a lack of light. Encounters between male and female Anglerfish are very rare. Scientists have discovered a way that these Anglerfish have solved their problem of infrequent meetings with one another. At first, researches found these lumps that looked like additional appendages on the female Anglerfish. Females were the only ones found for quite some time until they realized that these "appendages" were actually male Anglerfish.
Turns out that these male Anglerfish are approximately 40 times smaller than the females. To overcome this problem of little encounters between the male and female in the large, dark sea, these Anglerfish have developed a mating process. The males will bite onto the female when they are found. There is a digestive enzyme that when the male bites the females skin, she will digest his. Over a period of time, the male Anglerfish fuses with the female. Her nutrients will go to the male, who only has his reproductive organs left, through her blood stream which is now his too. Whenever the female is ready to reproduce, she can command the remaining parts of the male gonads to release sperm. Now she can lay her eggs and reproduce.

Anglerfish Video

Posted by Ryan Dulmaine (7)

Sources:

http://en.wikipedia.org/wiki/Anglerfish

http://www.thethinkingblog.com/2007/05/unusual-mating-habit-of-anglerfish.html



Thursday, November 17, 2011

Man-Eating Super Snake o_O

(Image curtsey of Google.Images.com)

"These invasive predators are causing severe damage to our native wildlife, and they need to be eradicated."

People continue to seem naive in realizing that introducing a foreign species to a new habitat can play out to have negative effects for either that organism or those who inhabit that environment already... or both. Southern Florida is faced with an epidemic of an invasive species. A hybrid cross between the African Rock Python with Burmese Pythons has converged to form what is being referred to the “Man-eating Super Snake.” What has been antagonistically depicted in movies has become a genuine threat in the Everglades.

African Rock Pythons are known for being giant lethal constrictors and one of nature’s most hostile reptiles. Another vicious predator snake is the Burmese Python. Neither of these are native species of the United States, and both are invasive species. Many consider these to be exotic pets but their owners soon realize that they are simply too much to handle. In captivity and in the wild, both these species have attacked and killed humans. The worst part is that once the snakes grow too big or too intimidating to care for, these people drive out to the Everglades and release them into the wild. This has proven to be detrimental to the people populating neighboring communities, native animals, and the entire ecosystem.

African Rock Pythons and Burmese Pythons were never meant to share a habitat, for more reasons than one. Aside from both being equally deadly constrictors, they have shown to mate in captivity. If such behavior occurs in the wild, Florida will find itself fighting a losing battle against the hybrid offspring− man-eaters. This hybrid is even more invasive and exponentially more deadly. The hybrid vigor poses an all too real threat to animals and man in Southern Florida.

As dangerous as they are as pets, many people still go out of their way to possess this “exotic” animal. They cannot be bought in any pet store, so these ambitious people turn to the black market where supply and demand fuels this industry. Those who do own an African Rock Python or a Burmese Python are required by law to obtain a permit and to have a microchip ID inserted into the snake. And there are designated locations where one could take their unwanted pet python, yet still, illegal release in the wild still occurs. In an attempt to further the ecosystem conservation, authorities have set designated hunting seasons for residents. It’s a “see a python, kill a python” campaign. The fight against this vicious behemoth is in full force, but this is in hope that it is not too late.


(Picture curtsey of the Miami Herald)


Sources:

Animal Planet: Man-Eating Super Snake

http://miamiherald.typepad.com/nakedpolitics/2011/06/tom-rooney-and-the-man-eating-super-snake.html#ixzz1e0kA3mVY


Post Created by Jose Mijangos


Wednesday, November 16, 2011

Drag Queens of the Animal Kingdom

Males of a species of bird known as the marsh harrier have been known to look and behavior like females. Whereas some birds of prey take pride in their masculine characteristics, these birds have no shame in "dressing" in drag. They engage in this behavior in order to fool other males, as to avoid potential conflicts. Surprisingly, these she-males can still successful mate with females and are able to establish territories despite their misleading appearance. "Permanent female mimicry" has been determined to occur in forty percent of all sexually mature male marsh harriers. These lifelong female behaviors and attributes have also been found in other species, particularly ones where males encounter numerous fights with other males, such as in fish, insects and reptiles.

Audrey Sternalski, a researcher at the Instituto de Investigación en Recursos Cinegéticos in Spain, and her colleges François Mougeot and Vincent Bretagnolle, conducted an experiment in order to test their theory that this adaptive behavior of female mimicry could be a ‘permanent non-aggressive pact” that has been made between males. During different stages of their breeding cycle, they set up plastic decoys to each bird group that represented three different bird types; males, females, and she-males. The researchers found that males were aggressive to the male decoys, but seemed more tolerant of the she-male decoys. She-male birds were tolerant of both she-male and male decoys, yet were observed to be aggressive towards the female decoys. Sternalski attributed this behavior to the fact that the she-males mimicking female behavior by defending breeding resources.

Randolph Krohmer, an associate professor of biology at Saint Xavier University, studied this female mimicry phenomenon in red-sided garter snakes, which do not physically look like females, but release pheromones that usually secreted by females. He found that during courtship, these species of snakes form mating balls that contain about 50 males and only one actual female. Since snakes can detect odors with their tongues, they often “taste” the scent that the she-males give off and spend time trying to court them. The she-males use this opportunity to their advantage and score the girl. I guess snakes really are sneaky! Opposed to the marsh harrier, only about ten percent of the population of these snakes are females and seems to remain constant over the years according to Krohmer. If this trait were as advantageous as it seems, wouldn’t we expect to see this percentage to increase? Perhaps only more time will tell.

http://news.discovery.com/animals/she-male-birds-raptors-111109.html


Posted by Sara Corey (7)

Single Dads

There are endless examples of offspring reared by two parents, a group, no parents, or single parents. In some species both parents work together to feed and raise their young, but in other species, such as turtles, the offspring are left on their own to survive. The more common occurrence is that the offspring are raised by one parent, which is typically assumed to be the mother. For mammals this is a safe assumption considering the mothers give birth to their young and feed them with mammary glands. However, there are some examples of single dads in the wild. Almost everyone has heard of male seahorses who incubate the eggs for several weeks before hatching, but there are other examples as well.

Greater rheas are a flightless bird species from South America in which the male will build and protect a single nest. During mating season he will mate with up to twelve females who will all lay their eggs in his nest. Each females clutch consists of five-ten eggs, which means this dad may have to raise up to 80 hatchlings! He will then incubate the eggs for around two months surviving on very little food and raise the hatchlings until they are around six months old. They will very aggressively protect their young, even from female rheas.

Male Marmosets from South America will carry, feed, and groom their offspring and also act as midwives during birth. They groom the newborns right after birth. These primates live in groups of three to 12 individuals. Females typically give birth to twins, which is 25% of her body weight. Due to the high cost of birth for females it is predicted that males make up for this by raising the young.

Hopefully people start to give more consideration to the effort any parents in the animal world put into their young, both mothers and fathers!

Posted by Caitlin Descovich O’Hare (7)

http://scienceray.com/biology/some-of-the-best-animal-dads-in-the-animal-kingdom/

Tuesday, November 15, 2011

Bats Change Ear Structure to make Hearing more Flexible


Bats are unique mammals notorious for navigating in the dark to catch their prey. They find their enemies by emitting ultrasonic pulses and listening to the returning echo. A recent study in Science Daily found that certain bats are able to change the shape of their outer ear from one extreme to another in order to change their hearing.


Changing the shape of their ear changes the bat’s ultrasonic hearing pattern. This allows them to find and capture their prey extremely precisely. The speed at which they are able to change their ear shape is remarkable. According to researchers at Virginia Tech’s Department of Mechanical Engineering, the Horseshoe bat can alter their ear shape in about 100 milliseconds. A human blink can take up to two to three times as long. The Horseshoe bat can use their sonar system to maneuver through vegetation and identify prey even under the most difficult conditions.


The researchers from Virginia Tech have also been able to reconstruct the geometries of the outer ears from live horseshoe bats as they deform in these short time periods. The researchers found that the different ear configurations could suit different hearing tasks performed by the animals using computer analyses. The researchers are now focusing on the understanding of how the most capable biological sensory system can achieve their best performances. It is amazing how certain bats can adjust the shape of their ear and change the shape so quickly to locate their prey.


Posted by Ryan Brooks (7)