BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: extinction

Is De-Extinction Upon Us? The Woolly Mammoth is Planned to be Introduced Back on Earth by 2027

You may be familiar with the large Woolly Mammoth’s (Mammuthus primigenius) from the movie Ice Age. These animals had once roamed the Earth for thousands of years, only recently going extinct at the end of the Pleistocene Period. Scientists Ben Lamm and George Church are leading the research into the second ever human provoked de-extinction, planning to release the Mammoth’s in Siberia. With an initial $15 million dollars in private funding, the team has received an additional $60 million to help achieve the 2027 deadline.

The closest living relative to these Mammoths is the Asian Elephant. Having once shared an ancestor 6 million years ago, scientists are working on pinpointing the genetic differences that set the ancient species apart from their modern (living) cousins. Fragments of Mammoth DNA have been retrieved from their ancient fossils (One of my previous blogs I wrote about DNA in fossils!), making it possible for scientists to modify the genome of an elephant to produce something that would look and act like a mammoth. The team will try to create an elephant embryo with its genome modified to resemble an ancient mammoth. To do this, the scientists will need to remove DNA from an elephant egg and replace it with the mammoth-like DNA. Some traits the Mammoth’s will need is dense hair and thick fat to withstand the cold environment. Siegsdorfer Mammut

Some other challenges to this de-extinction process is the actual birth of a fetal Mammoth. Scientists have been able to create a sealed bag that can support a fetal lamb up to four weeks, but for the Mammoth to be successfully birthed, it will require an artificial uterus big enough to house a fetus for around two years, reaching a weight of 200 pounds (~22~ months). While this may seem like an impossible task to many, the researchers behind this operation have stated that they’re eager and confident that their expertise will prevail, showing the world that editing DNA can bring extinct species back to life.

This article connects to our most recent unit in AP Bio of genes, genetics, and DNA. As we know genes in DNA are what make each person different from the other. Physical traits are mostly represented through gene pools (genetics), such as the thicker fat needed for the mammoth to survive. DNA editing is a crucial step to bringing back this animal and the scientists are working carefully to create the closest representation of the extinct species. This goal cannot be succeeded without the things we learned in this unit!

The presence of Wooly Mammoths in todays world can help the Siberian tundra as it has been overruled by moss. The moss acts as an insulator for the permafrost soil from the cold temperatures, thus melting the permafrost and releasing harmful gasses such as methane and Co2 into the atmosphere. Mammoths are considered “ecosystem engineers” because they feed on the moss and provide a natural fertilizer with their waste. With the moss being broken up, it would allow the grasslands to come back which keep the soil from eroding and melting. Ecologists have imported bison into the tundra in an attempt to help the tundra return to grasslands, but they believe the Mammoth’s will be much more effective.

While the team is multiple steps away, facing many challenges not yet conquered, they are continuing to push on with their research, inching closer and closer to making this reality. If this mission is a success, it will open the door to numerous DNA editing opportunities, restoration of the Siberian Tundra, and will remain a great feat of human advancement.

Siberian tundra 05

Back from the dead? Tech Startup attempts to bring back the Dodo bird.

Perhaps the most widely known animal extinction is the famous Dodo Bird.  According to Brittanica, the dodo became extinct after European settlers disrupted its native Mauritius.  Extinction, as defined by National Geographic, is “the complete disappearance of a species from Earth.”  However, as reported by US News, new technological innovations hope to reverse extinction and bring back the dodo bird.

According to the article, a tech startup Colossal Biosciences hopes to use gene editing technology to bring back extinct species, such as the dodo bird.  According to MedlinePlus, “genome editing (also called gene editing) is a group of technologies that give scientists the ability to change an organism’s DNA.”  According to Beth Shapiro, A biologist at the company stated that the company intends to edit the genes of the non-extinct Nicobar Pigeon, a close relative of the dodo, to recreate the dodo, hundreds of years after its extinction.  

Dodo 1

Despite these promising advancements, because researchers intend to use the genes of a different species, and the conditions on the island are not the same as they are today, it will be nearly impossible to revive the dodo bird exactly.  For example, as reported by US News, Shapiro stated “it’s not possible to recreate a 100% identical copy of something that’s gone.”  

While these advancements are exciting, as US News stated, there could be significant drawbacks to bringing back extinct speeches.  As stated by ecologist Stuart Pimm of Duke University “There’s a real hazard in saying that if we destroy nature, we can just put it back together again – because we can’t.”  As stated earlier, it was colonists and mistreatment of the environment that caused the extinction of the dodo bird in the 1600s, so perhaps, as reported by US News and stated by Boris Worm of the Univerity  of Dahlhousie in Halifax, Nova Scotia “Preventing species from going extinct in the first place should be our priority.”  Perhaps we can achieve this goal by taking better care of the environment, for according to Columbia Climate School, “The main modern causes of extinction are the loss and degradation of habitat (mainly deforestation), over exploitation, (hunting, overfishing), invasive species, climate change, and nitrogen pollution.  Many of these ideas connect to what we have studied in biology class, such as the effects of genes.  According to Brittanica, Gene editing technology uses enzymes to influence genetic sequences; these enzymes are called Restriction Enzymes.  Additionally, according to the University of Illinois, “Restriction enzymes are essential tools for recombinant DNA technology.”  As we learned in the Mitosis/Meiosis, and cellular respiration unit, recombinants are the chromosomes that occur when chromosomes “cross over” during Prophase I of meiosis, essentially creating a blend of different traits.  This phenomenon is similar to what occurs in gene editing technology, where enzymes snip DNA, adding different traits, to create a sort of “mix” of traits.

 Therefore, while these new technologies in gene editing are exciting, we shouldn’t be 100% convinced of their effectiveness, and we should continuously question the ethics of such practices.

Bird Diving can Lead to Extinction

In this article, it talks about birds that are able to dive underwater what it does to them. There are three types of diving birds – foot propelled, wing propelled, and plunge divers. It talks about how these birds adapt to the environment and are able to get food by diving. This actually hurts some species of birds because they aren’t fully suited for it. Some birds that dive or plunge underwater aren’t meant to do this and could cause damage to the neck and bones in the chest. This is causing these birds to go extinct. This hurts the penguins the most because they are specialized in diving compared to other species of birds and the environments change which make it hard for them to adapt. The environments changes are caused by marine heat waves which affects the birds adaptation to the environment.

In an article similar to the main one, it talks about how when penguins are on land they are at a disadvantage compared to other species of birds even though they are the best at diving. Then there are other bird species like gulls that can adapt to eating food in the water and out.

 

In another article, it also talks about how body size matters when it comes to diving of bird species. Penguins use their wings to dive for food but can’t fly obviously. Cormorants for example use their feet to kick and swim underwater. The birds that use their wings have a large body and this helps them develop a larger body. So depending on what kind of diving the bird does. All these different traits make the biggest difference into why penguins and wing propelled divers are going extinct.

 

This connects to what we have learned this year in AP Bio because of the adaptions. When we studied plants this year, we understood what kind of things they needed to survive. For example we saw that the plants we grew in class this year needed a certain amount of light and water. It also connects with plants will use certain things for example their roots being able to pull the water throughout the rope that goes through the dirt.

Penguin in Antarctica jumping out of the water

 

 

 

 

Can extinct animals be resurrected?

Recently the CIA has been looking into “resurrecting” extinct animals, specifically Mammoths. Colossal Biosciences, a company based in Texas, believes they can genetically engineer the mammals’ DNA. Although it would be virtually impossible to bring Mammoths back from the dead, their goal is to insert their distinctive traits into present-day Elephants. For this process, scientists need to use “CRISPR,” a method used to replicate gene sequences. According to MedlinePlus, CRISPR “is a group of technologies that give scientists the ability to change an organism’s DNA…and allow genetic material to be added, removed, or altered at particular locations in the genome”. While some scientists are for this idea, others believe it is impossible and the time and money spent could be allocated elsewhere. Ben Shapiro, a professor of ecology and evolutionary biology at the University of California, stated “The biggest misconception about de-extinction is that it’s possible.” Even if scientists were able to collect preserved DNA from the animal, it is nearly impossible to replicate them using technology.

AP Biology Connection

All animal cells need oxygen, food, and water, so when they are deprived of it, they die. Cells consume these through a process called endocytosis. Endocytosis is a process in which cells pull substances from the outside and then engulf them in a vesicle. Without this process, not only would the cell die, but so would all of its contents. DNA is the cells “carrier of genetic information“. DNA itself is very fragile, and under no circumstances will it survive from the extinction of the Mammoths to the present day. Ancient DNA, such as the ones we have from Mammoths, has gone through many environmental issues. Elements such as sunlight, water, and heat can accelerate the DNA degrading process. Unless very well persevered by freezing and sealing it, the DNA will not be functional. The rupturing of cells, when dead, release nucleases causing damage to DNA. Although “bringing back” the Woolly Mammoth would be a great scientific revelation, it seems infeasible due to the inner workings and preservation of the cells.  Woolly mammoth (Mammuthus primigenius) - Mauricio Antón

“And Then There Were None.” Not An Agatha Christie Murder Mystery, but an Eye-Opening Story of Extinction

 

A Land Snail

George the Snail

On January 1st, while we were all blissfully celebrating the transition from 2018 to 2019, the last land snail of the species Achatinella apexfluva, which had thrived for many years on the Hawaiian island of Oahu, had gone extinct.

The name of the snail was George. It was given to him by researchers so that he may be remembered and not simply become an extinct species left unknown to most. Researcher Michael Hadfield notes “You anthropomorphize it [i.e. George the snail] and people pay attention.” More importantly, though, is George’s story. He was “…born in the early 2000’s to parents that had been captured in the mountains [by scientists] in an effort to protect them from predators.” Then, there was a sudden mass extinction event. What researchers believe to be some form of a pathogen annihilated the remains of George’s already endangered species. George was the lone survivor of this unfortunate phenomena.

George’s species is not the only one to face extinction on the Hawaiian Islands. “At one point there were more than 750 species of land snails identified…” George’s species, however, was the first. Unfortunately, Dr. Sischo, who directs the state-run Snail Extinction Prevention Program, mentions that estimates say that “more than half of those species are already extinct.” There were other factors, other than the elusive pathogen, that have afflicted the land snails over a much longer period of time: “…invasive predators like rats and wolfsnail, which eats other snials. They also face habitat destruction and the effects of climate change; drier conditions have reduced the inhabitable land on the islands,” Dr. Sischo says.

In 2017, researchers removed a two-millimeter section of his foot and have preserved it in a “deep-freeze container” according to the Department of Land and Natural Resources. “The hope is that someday soon, scientists will develop the technology to clone a snail.”

Survival of the Fittest or Laziest?

For hundreds of years biologists have essentially fully accepted Darwin’s theory of “Survival of the Fittest;” but, have they been wrong all this time? Scientists believe that there could be a link from high metabolic rates to extinction. Luke Strotz, scientist and researcher at the University of Kansas, studied the effect of metabolic intake, energy intake by an organism, in mollusks.

Strotz and his team decided to use mollusks as their objects of interest due to the sheer abundance of data that they could retrieve from the past 5 million years. Strotz observed that certain mollusk species with higher energy intakes are extinct; while, mollusks species that have considerably lower metabolic intakes are still in existence today. Thus, in the mollusk group, it was quite clear that the higher metabolic rate correlated with faster extinction. Although this study is quite primitive in nature, and thus should not be compared to humans, it is perplexing to see that a species in the mollusk group can continue to exist because of its “laziness” or low metabolic intake.

Although Strotz’s evidence is convincing, I personally do not believe that “Survival of the Laziest” should be taken seriously, as mollusks are extremely different from humans. Thus, it would be illogical to compare the correlation of this study to that of the lives of humans. So, unfortunately, it appears laziness is most likely not a trait that the human race should endorse.

What do you think? Can laziness really save the human race? Only time will tell.

 

The research from Luke Strotz is published in the journal: Proceedings of the Royal Society B.

 

The Silent Extinction: How an invasive species is likely to destroy the Ash Tree

There is a mass extinction occurring right now all across North America that millions of people have never hear of. First discovered in North America in 2002, the Emerald Ash Borer, an invasive species native to Mongolia and northern China, has destroyed tens of millions of Ash Trees across North America; and it is likely to destroy millions more.

The Emerald Ash Borer does its damage as larvae. They burrow into the bark of Ash Trees to protect against the cold and in the process of this, cut off the nutrients and water the Ash Tree needs. Scientist suspect that the Emerald Ash Borer has been in North America at least ten years before it was detected.

The devastating effects of the Ash Borer go far beyond losing a tree on your property or favorite hiking trail. The destruction of Ash trees could have a chain effect that leads to the endangerment of numerous plant and animal species. The removal of the canopy that the Ash Trees create leads to sunlight hitting spots of the forest floor that it previously did not. This could lead to invasive species of thickets and bushes covering the forest floor, preventing native plants from growing. Which, in turn, would lead to animals that inhabit the forest going without some of their primary food sources.

In the past, invasive insects have been fought by a combination of insecticides, awareness, and felling of infected trees. This proved fairly successful with the Asian long-horned Beetle in Chicago, but the Emerald Ash Borer presents a different set of challenges. Firstly, the Emerald Ash Borer is march harder to spot than the more distinctive Asian Asian long-horned Beetle. Secondly, it is much easier to deal with an invasive species when it is still localized. While the long-horned beetle was still mostly confined to Illinois, the Ash Borer has spread all across the Upper Midwest.

All factors considered, it may seem that there is nothing that can be done. However, with increased awareness, improved insecticides, and new containment techniques there is hope. The fate of millions of Ash Trees depend on that hope.

For more information click here

 

 

 

Tree Lobsters Are Back!

Image result for Stick insects Tree lobsters Lord Howe

Lord Howe Tree Lobster

Tree Lobsters are actually not lobsters at all. Nor are they crustaceans.  They are actually just insects with a similarly shaped exoskeleton. But that’s not what makes them interesting. What does, is that Tree Lobsters have seemingly come back from extinction.

The Species, originally from the Lord Howe Island in the Tasman Sea between Australia and New Zealand, went extinct during the 1920’s due to becoming the main food source for an invasive rat species that came onto the island. The Tree Lobsters were only formally declared extinct in 1960 though. Since then scientist had pretty much forgotten about them.

Image result for Stick insects Tree lobsters Lord Howe

Ball’s Pyramid Stick Insect

Thus, when scientists found a small group of stick insects similar to Lord Howe Tree Lobster’s on Ball’s Pyramid, a volcanic stack 12 miles away from Lord Howe Island, in 2001, they were quite surprised. The Ball’s Pyramid stick insects were skinnier and darker but scientists were still hopeful the newly discovered insects were, in fact, the same species as the extinct Lord Howe Tree Lobsters. Scientists tested the genes of the stick bugs from Ball’s Pyramid with genes extracted from preserved Lord Howe Tree Lobsters and found out that despite some morphological variance, they are still the same species. They speculate that diet, age, and environment had caused the Ball’s Pyramid Stick Insects to look a little different. How the species got to the volcanic stack is still a mystery as the insects cannot swim but they infer that they had been carried over by birds.

The newly discovered Tree Lobsters are now being bred at the Melbourne Zoo and elsewhere in an attempt to reintroduce the species to Lord Howe Island. However, the invasive rat species on Lord Howe Island still remains a problem as it threatens the lives of over 70 different native species. In order to successfully reintroduce the Tree Lobsters back to Lord Howe, the rat problem needs to be taken care of first.

Back from the (almost) dead: Burmese Star Tortoise

The Burmese Star tortoise trade is very lucrative, but also very harmful. Poachers make money by capturing them in their natural habitat of Myanmar (formally Burma) and selling them as exotic pets. The Burmese Star tortoise was classified functionally extinct, meaning their population was so small that it was no longer able to sustain itself.

Herpetologist, Steven Platt, set up breeding colonies in Myanmar. In 2004, they captured less then 200 tortoises from the wild and put them into three breeding colonies. This was a large enough starting population to avoid inbreeding. Today the number of tortoises they have has grown to 14,000! In 2013, about 1,000 tortoises were reintroduced into protected land. In 2016 these colonies produced over 2,000 hatchlings per year.

https://commons.wikimedia.org/w/index.php?search=burmese+star+tortoise&title=Special:Search&go=Go&searchToken=aoyyrtn0pqlw6dhkgvfep0gdi#/media/File:Birumahoshigame.jpg

Despite the massive success of the breeding colonies there have been setbacks. At first, poachers broke into the breeding colonies to steal the tortoises. Modifications, such as 10 foot concrete walls, were installed to protect the tortoises from the thieves. After the tortoises are reintroduced into a protected area there is still the concern of poachers. However, with the success of the breeding colonies, that were started by confiscated tortoises, there is a lot of promise that this species will survive going forward. A new idea to reintroduce this species is the bury their eggs and let them hatch in nature. Dr. Platt hopes this will speed up the re-establishment of the population.

Dr. Platt recognizes that he and his team can not reintroduce the Burmese Star tortoise effectively without community support. By sharing their work with the near by community, members of it look of for illegal activity and are willing to help in any way they can. Dr. Platt’s group also gets local monasteries to bless the tortoises which supports the local theory that harming a tortoise will result in “divine retribution”.

 

 

Thylacine Brain Structure Reveals Predatory Lifestyle

The thylacine, also known as the Tasmanian Tiger, was the largest carnivorous marsupial of modern times. Native to Australia, Tasmania, and New Guinea, the thylacine quickly went extinct at the start of the twentieth century, following an increase of demand for its pelts. The last known thylacine died in 1936, in Beaumaris Zoo in Hobart, Tasmania, and little is known about the species’ natural behavior. New research however, gives humans a better glimpse into brains and programming behind one of Australia’s most fascinating predators.

Dr. Gregory Berns of Emory University and Dr. Ken Ashwell of the University of New South Wales scanned thylacine brains and reconstructed neural connections in an effort to better understand the specific functions of the thylacine brain and behavior. Only four surviving specimens of the brain exist, and their study gained access to two of them.

“One was provided by the Smithsonian Institution, taken from a male Tasmanian tiger after it died at the National Zoological Park in 1905. The other specimen, loaned to the researchers by the Australian Museum in Sydney, came from an animal that died during the 1930s.”, claimed researchers.

They compared the structure of Thylacine brains to those of Tasmanian devils. The researchers found that the thylacine brains had larger caudate zones than the Tasmanian devil brains. This suggests that thylacines devoted more of their brains to complex thinking, particularly action planning and decision making.

These findings match with what we know of the two animals. Tasmanian devils are known to be scavengers while thylacines were hunters. The neural rewiring done by the researchers provides anecdotal evidence that thylacines occupied a more complex predatory brain than their scavenger cousin, the Tasmanian devil.

These findings are fascinating because they give us new information regarding an animal less than 100 years extinct. It’s seems strange that we had never gathered much information about the thylacine prior to its extinction. However, the resurgence in fascination and curiosity about the animal is exciting to see. Hopefully new research and discoveries will be made in the near future, shedding more light on the thylacines life.

 

 

Image result for thylacine

Source Article: http://www.sci-news.com/biology/thylacine-brain-structure-04549.html

 

The Dangers of De-Extinction

uploaded by: FunkMonk
https://commons.wikimedia.org/wiki/File:Woolly_mammoth.jpg

Our once ludicrous dream of resurrecting our dead animal friends, like the wooly mammoth, is transforming into a real possibility! According to David Schultz’s article on Sciencemag.org, due to human advancements made in the study of genetic engineering, scientists at Harvard University were able to reach new heights in the efforts to tackle de-extinction. However, now that it is almost within man’s capability to actually bring back extinct animals, there is a spark of skepticism sweeping the scientific world. “The conversation thus far has been focused on whether or not we can do this. Now, we are progressing toward the: ‘Holy crap, we can—so should we?’ phase,” states ecologist Douglas McCauley. McCauley shines light on the sudden realization of how resurrection may be exciting, yet also very demanding and potentially harmful. Due to tight funds, it is believed that resurrection of one extinct animal can harm the life that is already struggling to be sustained on earth.

In order to reach this financial conclusion, researchers sought out databases in New Zealand, Australia, and New South Wales that are responsible for tracking the cost of conserving endangered animals. With this information from the databases, the researcher team believed that it would cost just as much, if not more, to maintain a resurrected species as it would an endangered species. What this means is, that the already tight funds that conservationists have to support endangered animals would be stretched immensely in order to fund the conservation of a newly resurrected wooly mammoth species, for example. Schultz writes, “The result, the team calculates, would be an overall loss of biodiversity—roughly two species would go extinct for every one that could be revived.” Because of the world’s budget for species preservation, and as author and biologist Joseph Bennet says, “It’s better to spend the money on the living than the dead.”

With that being said, it appears that our excitement around bringing the dead back to life has been faded by the the reality of our world’s finances. Though the study of extinction is still vast, perplexing, and amazing, the application of our resurrecting abilities may not happen anytime soon. Would you like to someday walk on the earth with our old prehistoric animal friends or would you rather save the world’s endangered species first?

https://phys.org/news/2017-02-resurrecting-extinct-species-terrible.html

 

A Brand New Dinosaur? Just When You Thought There Were No More Dinosaurs.

 

Yep, you read that correctly, a brand new dinosaur(…’s skull) has been found in the Patagonia region of south America. Its amazing that after millions and millions of years new dinosaur fossils are still being discovered which can lead to the recognition of a whole new species of dinosaur. In this case, the dinosaur was part of the pterosaurs group, which is a extinct group of “flying reptiles”. This brand new type of dinosaur was named Brain Ancient; just kidding, its name translates to “brain ancient” its really called “Allkauren Koî”. But why was the dinosaur named this? These two additional websites may help answer that as well as show what the dinosaur might have possibly looked like. The name was probably given to this extinct animal because all that was found of it was an ancient brain(in reality the skull and part of the backbone and vertebrae was found). This find shows just how interesting the world used to be and it still amazes me that we are able to find remains of the beasts that ruled the world before humans.

 

williston_pteranodon

 

Here is the fossil of a close relative of this newly found dinosaur (this dinosaur is in the same group, pterosaurs). S.W. Williston’s reconstruction of Ornithostoma ingens, a synonym of P. longiceps

 

To clarify, if you would like to see pictures, that can’t be shown on this article due to copyright issues, of what this new dinosaur Allkauren Koî might have looked like, you can use these two links that are shown below.

http://www.natureworldnews.com/articles/27867/20160831/fossil-of-new-species-of-flying-dinosaur-found-in-argentina.htm

http://www.sci-news.com/paleontology/allkauren-koi-argentina-04145.html

 

 

 

SAVE THE BEES!

What is happening to bees?

The media has been buzzing lately about bees! Pesticides and fungicides have long been thought to be problematic for our yellow, fuzzy, pollinator friends, but never more-so then now; 7 species of bees have been officially placed on the US Endangered Species List. In fact, a UN sponsored report revealed that over 40% of pollinator species such as bees and butterflies are facing extinction. This is an incredibly dangerous statistic, as 75% of the world’s food supply depends at least partly on pollination.

This rapid decline is forcing scientists to reexamine the use of pesticides on crops and bee colonies, and begin to think holistically. It’s a concept reminiscent of cancer research, calculating the “exposome,” or the net amount of pesticides an organism is exposed to over its lifetime.

When investigating the health of bees it is important to consider the colony as a single “super-organism” led by the queen bee, rather than individuals. On average, a queen bee will live for around two years, but lately queens haven’t been making it through a single season. Sometimes, the colony is able to replace her, but often they cannot. The loss of a queen can end in death for the entire colony.

Why is this happening?

After following almost a hundred colonies owned by three different beekeepers, for a full agricultural season, researchers from the University of Maryland found a total of 93 different pesticide compounds that came in contact with the bees. Some of these accumulated in wax, pollen and even the bodies of Nurse Bees. After further tests, they found between 5 and 20 different pesticide residues in every sample that exceeded the “hazard quotient”, or amount of a toxin an organism can handle. One surprising finding concerns fungicides, an alternative long thought to have been bee-friendly. In fact, these fungicides tended to have even more deadly effects on Queen Bees.

What can we do?

Ultimately, these findings, coupled with the rapid decline of bee population nationally shows us that we as humans are undeniably at least partly responsible for the decline of bee population. Bees are crucial to our way of life, and we should do everything we can to protect them. By supporting sustainable agriculture practices, and farms that use alternative forms of pest and fungus control, you too can do your part to save the bees.

 

Only the Small Survive

Small fish featured in its natural niche

Small fish featured in its natural niche

http://www.pdpics.com/photo/1329-small-green-fish/

With many large species such as giraffes and sharks threatened with extinction, we might not see the likes of them for millions of years.  History has shown that evolution cannot restore large species for tens of millions of years.  Intrigued by this concept, paleontologist Lauren Sallan of the University of Pennsylvania sought to know why small species are able to bounce back much quicker than larger species.  Looking at aquatic life of the Mississippian Period, from 359 to 323 million years ago, she observed that most fish were significantly smaller than their ancestors.  This idea that certain species generally shrink over time is known as the Lilliput Effect, named after an island indigenous to tiny people in Jonathan Swift’s Gulliver’s Travels.  The fossils used in Dr. Sallan’s project fit this description as their ancestors probably perished perished in the deep freeze brought on at the end of the Devonian Period which wiped out an estimated 96 percent of all vertebrates.  However, the Lilliput Effect does not apply to all species.  One species, known as the rhizodontids, included fish that grew to the size of modern day killer whales.  Dr. Sallan concluded that the painfully slow recovery of large species on this planet is due to the ecosystems decimation during mass extinction events.  Although this particular article does not go into depth on why small animals have an easier time “bouncing back” than large ones, Dr. Sallan examined many fossils which prove that creatures shrank dramatically after large-scaled extinctions.  For example, the average size of a shark shrank from about a yard in length to only a mere few inches.  However, later in the article, Dr. Sallan cites her study by saying how smaller vertebrate species produce and diversify more easily contrary to large vertebrate animals dwindling in diversity until species extinction.

Original Article: http://www.nytimes.com/2015/11/13/science/after-a-mass-extinction-only-the-small-survive.html?rref=collection%2Fsectioncollection%2Fscience&action=click&contentCollection=science&region=rank&module=package&version=highlights&contentPlacement=2&pgtype=sectionfront&_r=1

Other Interesting Articles:http://science.nationalgeographic.com/science/prehistoric-world/mass-extinction/

http://www.pbs.org/wgbh/americanexperience/features/general-article/dustbowl-mass-exodus-plains/

Fossils of Massive Rats Found

Attention fellow biology lovers: it appears our biggest fears have been realized. In East Timor, in Southeast Asia, researchers have found fossils of rats up to ten times larger than modern rats. Fear not, however, as these rats are long gone. Researcher Dr. Julien Louys said that the rats lived tens of thousands of years ago, and that there is evidence of humans actually using them as a source of food. Many of the fossils were found with cut and burn marks. The findings came as a part of a project called From Sunda to Sahul. The purpose of the project team that found the rat fossils was to find when humans started moving through Southeast Asia.

Dr. Louys believes that the rats actually lived in Southeast Asia until about one thousand years ago. He cited their extinction as being cause by the introduction of metal tools into society in Southeast Asia, enabling the inhabitants to destroy forests faster and more completely. The team is working to find the impact of humans on the Southeast Asian Ecosystem, which is directly correlated to the rats. Once they find the exact conditions that existed in the area before the rats extinction, they will have a more exact idea of what happened that left the rats extinct.

The rats themselves are characterized as mega-fauna. Mega-fauna is a term that refers to animals that are abnormally large, and these rats fall under this category. The rats are part of a movement that has seen a mass extinction of mega-fauna animals across the globe. Although the most common explanation for this unfortunate trend is human influence- which undoubtedly played a role- the reality is that hard evidence points to climate change as having a larger impact. As more research takes place, it will become clearer as to the exact reason for extinction of these massive rats in Southeast Asia. What do you think caused the extinction? Feel free to comment!

A sketch of a Deinotherium, a mega-fauna species that went extinct about 12,000 years ago. Image from Wikipedia Commons.

 

 

The Immaculate Conceptions: Smalltooth Sawfish Experiencing Virgin Births

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From Flickr

Chances are you have never heard of the Smalltooth Sawfish, an endangered species most commonly found off the western cost of Florida. These creatures grow to be as long as 25 feet, but their is more that is impressive about these fish than their shockingly large size. Recent studies have shown that around 3% of Smalltooth reproduce asexually, a virgin birth. This is the first hard evidence that birth of parthenogens, offspring born of asexual reproduction, happens in nature. This speaks to the adaptability of life, scientist Demian Chapman, says that it makes sense that endangered species would be the ones most commonly reproducing asexually, “that life finds a way”. This discovery was made when researchers tagged and sampled DNA from around 190 Sawfish, which lead to the discovery of 7 parthenogens.

Scientist hypothesize that during meiosis, sex cells fused together to form offspring. Incredibly, all seven of the parthenogens are fully healthy and functioning, and seem to be viable sexual partners. This “suggests that parthenogens are not a dead end” that this “extreme form of inbreeding” does not lead to any serious defects. Unfortunately, Smalltooth Sawfish are on the verge of extinction due to human interference in their natural habitat. Although the Sawfish are able to reproduce asexually, the occurrence rate is too small to sustain a viable number of Sawfish to save them from extinction, but raising awareness of the issue could be the key to saving these magnificent creatures.

 

Original Article

Sawfish Extinction

More Examples of Parthenogens in Nature

Serious Monkey Business Going on with these Tanzanian Monkeys

https://commons.wikimedia.org/wiki/File:Udzungwa_Red_Colobus_Stevage.JPG

https://commons.wikimedia.org/wiki/File:Udzungwa_Red_Colobus_Stevage.JPG

A team from the University of Oregon comprised of Maria Jose Ruiz-Lopez, a postdoctoral researcher, and Nelson Ting, a corresponding author and professor of anthropology, have discovered why a specific species of endangered monkeys in Tanzania are living in various different geographical areas that are increasingly becoming isolated from one another. It has been concluded that this situation is due to the monkey’s closeness to villages and the intentional forest fires by humans in an effort to create space for crops. Lopez collected 170 fecal samples of the Udzungwa red colobus monkey, a specific monkey used as indicator species in ecological change, for DNA analysis over five distinct forests in the Eastern Afromontane Hotspot. To approach this experiment, the team used landscape-genetics, a method that merges landscape ecology and population genetics. Though odd to use in tropical settings, this technique allowed them to investigate the dissimilarities between 121 monkeys and how human activity influences ecological changes. The largest difference between monkeys were of those who were separated by villages and/or zones that had a history of the highest density fires. The researches studied multiple variables at once and the monkey’s proximity to villages and man-made fires was still the most significant. Because these fires are stopping the monkeys from migrating, smaller groups of them are becoming more isolated, resulting in a decrease of genetic diversity and yielding to extinction variables.

This experiment regarding behavioral ecology, a way in which organisms react to abiotic factors in their environment, made me contemplate the human’s role in the environment and how we are strongly affecting the possible extinction or conservation of animals. This particular ecosystem is rich in diversity and it would be a tragedy for it to fall to extinction! There is no direct solution to this problem; after all, to have the power to alter a human’s ecological footprint and their decision whether to burn a forest or not is quite hard to seize control of. Do you believe with enough awareness and education, local communities would be able to create a local solution to save the diverse genes of these monkeys?

Original article can be found here.

Why Climate Change shouldn’t Always be the Scapegoat

Seychelles,

A certain purplish-blue banded snail was rediscovered after initially deemed extinct by the general scientific community, stirring up the minds of the many who continue to debate the effects of climate change and what living things directly suffer its consequences. Firstly declared extinct by a highly regarded Seychelles mollusk expert, Dr. Justin Gerlach, the snail’s reclassification has caused backlash in the scientific community. With such a confident course of action in not only the declaration of extinction, but also the citing climate change as the primary reason, it is understandable and necessary that scientists should view this case with scrutiny and care. Gerlach attributed an insufficient amount of rainfall to the snail’s extinction, which he suggested was in direct association with climate change. Not alone, other scientists also backed his claims, agreeing that climate change caused immediate ramifications for this banded snail.

However, with the rediscovery of this snail, it is now essential not to overestimate the weight of climate change when discussing extinction and habitat loss, although we know climate change is a very real and growing concern. According to the UN’s panel on climate change there are more than a few other factors that can impact a species that can also sit in the shadow of climate change in inappropriate manners. It is irresponsible to use climate change as a scapegoat in certain situations, as it can prove to be detrimental in the future when in hindsight it may not have been the primary causation of a species decline. The UN panel provides us with data that reinforces the notion that mollusks suffer from extinction based on factors like pollution or invasive species. As Bjorm Lomberg suggests “climate change is a real problem, but the way it is increasingly blocking sensible thinking is depressing.”

As for the future, the rediscovery of this species can hopefully serve as an example of the disillusionment that can arise from a hyped phenomenon. Yes, climate change is one great problem, but it is one of many, and we must hold ourselves accountable to where our conclusions derive from. The only current certainty is that we have to do a better job at limiting these debilitating  factors.

Further Reading/Sources:

http://www.ctvnews.ca/sci-tech/seychelles-snail-believed-extinct-due-to-climate-change-found-alive-and-well-1.1996871

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

http://www.forbes.com/sites/paulrodgers/2014/09/20/extinct-snail-rediscovered/

http://news.mongabay.com/2007/0813-snail.html

http://islandbiodiversity.com/jg.htm

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

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

Birds and Migration: More Than Just the “V-Formation”

birds

For as long as we can remember, we have known that many species of birds migrate south during the winter, in a “V-formation.” Recent studies by ecophysiologist Steven Portugal have suggested that the classic formation helps birds to conserve the most energy possible. His investigation involved researching the Northern Bald Ibis, a bird that was extinct in Europe for around 400 years. Johannes Fritz has been working tirelessly to bring the Northern Bald Ibis out of extinction, by pioneering an human-led migration throughout Europe, for the past 12 years. (To discover more about these birds, and their emergence from extinction in Europe, check out this site.)

Through his studies, Steven Portugal has identified that his hypothesis was correct; the “V-Formation” does, in-fact, help a flock of birds conserve the most energy as well as “the birds’ formation fitted the theoretical predictions of aerodynamics.” The birds synchronize their flapping when they experience turbulence. He also found that the birds break their arrangement to those of “less-optimal positions.” This includes, birds going one-behind-the-other, and changing their wing-flapping patterns. This is all believed to prevent downwash, which is “the downward deflection of of an airflow,” as defined by the dictionary.

Thanks to the work done by Steven Portugal, Johannes Fritz and their respective teams, we have come much closer to discovering “the why” in bird-behavioral patterns, namely their flock formation during migration.

Tasmanian Devil Extinction on the Horizon

The tasmanian devil is most readily remembered by it’s cartoon character, however the extinction of the animal seems to be on the horizon. Tasmanian devils are wild animals of the Dasyuridae family found only in the wild of Australian island of Tasmania. Recently, it has been predicted that a facial cancer on the marsupial will extinct the species in the next ten years.

First reported in 1996, the parasitic tumor has declined the species by seventy percent. The onset of the non-viral tumor was caused by the environment of the animal (who live in high-density populations that suffer from invasions of nonnative species and pollution.) Devil facial tumor disease likely began in what are called Schwann cells. Schwann cells are found in the peripheral nervous system; they produce myelin and other proteins essential for the functions of nerve cells.

Scientists are trying to remedy the infectious disease by breeding a certain species of tasmanian devil that was shown to have a partial immunity to the tumor. After preliminary research on the disease, scientists have come to see that the answers to the tasmanian devil’s circumstance, if uncovered, could lead to answers for human cancers as well. More knowledge of the direction and rate of the tumor in devil populations will help scientists to find out more about how the disease spreads byYoung_tasmanian_devil examining the interactions between the animals. Scientists remain positive; Andrew Storfer, who works closely with the animals on location, says “the answers will help in developing responses to this and other disease outbreaks in Tasmanian devils–and potentially in people.”

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