Scientists have confirmed that three babies produced by a female zebra shark in Townsville City, Australia, were conceived asexually. Although this shark, named Leonie, had shark babies with a male partner in the early 2000s, aquarium workers noticed Leonie was pregnant yet again in early 2016.

Sure enough, three baby sharks were birthed later this year. Although asexual reproduction is rare in sharks, scientists have known for awhile that many vertebrate species have the ability to reproduce both sexually and asexually.

Background On Leonie’s Case

Leonie was first put into the Reef HQ Aquarium in Townsville City in 1999. She had a male partner with her at the beginning. Over the years, Leonie had some two dozen babies with the male shark. Then, in 2012, the aquarium staff decided to move the male shark out of Leonie’s tank to give her some privacy. From 2012 until today, Leonie has had no male contact.

After these years of isolation, Leonie suddenly produced three shark offspring in early 2016. This quickly caught the attention of local researcher Christine Dudgeon, a professor at the University of Queensland in Brisbane, Australia.

At first, Dudgeon and colleagues thought that Leonie must have stored sperm from her male mate and only chose to use it to fertilize her eggs much later. However, after testing Leonie’s three new children, researchers discovered that they only contained the DNA of her mother. There were no traces of the father’s DNA in these three little sharks.

This discovery made it clear that Leonie must have reproduced these offspring asexually. As mentioned before, this isn’t the first time a vertebrate has been observed asexually producing children. Scientists have documented Komodo dragons, eagles, and boa constrictors doing the same thing.

The interesting thing about Leonie’s case is that she switched from sexual to asexual reproduction exactly when her external conditions demanded she make an adaptation. This leads many in the scientific community to wonder just how common asexual reproduction is in the wild.

What Scientists Are Learning From This Zebra Shark

Scientists note that Leonie’s case is the first time on record they’ve observed a female zebra shark making the switch from sexual to asexual reproduction so quickly. Researchers say this decision to reproduce asexually clearly shows the importance of external pressure.

It also proves many animals that reproduce with partners have the ability to reproduce on their own if they feel the need to.

The actual biological function that allows this sexual/asexual switch is still unknown to scientists, but Leonie’s case offers a few more clues into its evolutionary function.

Dudgeon argues that the asexual function in female zebra sharks might be “a holding-on mechanism” so that a mother’s “genes get passed down from female to female until there are males available to mate with.”

In addition to learning more about this asexual reproductive function, researchers now have a clearer sense of the evolution of zebra sharks over time. Over the course of the species’ history, there are many periods of sharp reductions in the zebra shark population.

These declines often occurred during ice ages. Dudgeon believes that during these periods of population decline females must have preserved the species by reproducing asexually.

Hope For The Survival Of Zebra Sharks

The news of Leonie’s asexual reproduction isn’t only helping scientists better understand this mysterious evolutionary adaptation, it’s also giving them hope for the future. Zebra sharks are now considered a vulnerable species. The main threat to their survival comes from inshore fisheries.

Still, if female zebra sharks adapt to their circumstances and can start reproducing asexually, many marine biologists are hopeful zebra sharks will make it into the future just fine.

Image source: pexels.com/photo/underwater-no-person-water-fish-108056/

New data shows that the Arctic’s floating sea ice levels are the lowest ever recorded. Although we’ve only been monitoring the earth’s sea ice levels with satellite technology since the 1970s, some scientists believe this could be the lowest level ever. Meteorologists around the world are pointing to this data as yet another warning sign of the disastrous implications of global warming.

How Bad The New Data Really Is

This new satellite data comes from the U.S. National Snow & Ice Data Center located in Boulder, Colorado. On this center’s latest graph, which was officially published on January 14th, Arctic ice levels are documented from 1978 to the start of 2017. It is clear to spot the outlier in the 2016 line.

This red line dips well below the average during the months of October, November, and December. Most scientists, perhaps unsurprisingly, believe global warming played a key role in this year’s decline. To further prove their point, scientists also point to another graph that details the shrinking Arctic sea ice levels during the winter season.

Yet another graph released by the Snow & Ice Data Center shows how Antarctica’s sea ice area has been shrinking rapidly during the southern summer season. However, most meteorologists are not screaming in panic just yet over these Antarctica numbers. Although these numbers aren’t great, many climatologists believe 2016’s low Antarctica number was exacerbated by natural temperature variability.

John Turner, who works as a climatologist for the British Antarctic Survey, believes the main reason we see this low number for the 2016 Antarctica ice levels has to do with the weaker winds found around Antarctica. Turner told reporters that Antarctica’s climate is “extremely variable,” and that slight changes in winds “can have a huge effect on sea ice.”

Scientists Focus On Arctic Numbers

It’s the data surrounding the Arctic that has more climatologists worried. Since the Arctic’s ice levels have been in a steady decline for decades now, most meteorologists believe it must be due to the increased pressure from global warming. Warm air is entering into the Arctic, which causes the ice to melt more rapidly over time.

This would explain why many nations in both Europe and Asia experienced extremely low temperatures last year. As the warm air moves into the Arctic, it pushes all the cold air out into these continents.

Eric Holthaus, a popular meteorologist on Slate, took to social media after analyzing these Arctic numbers. Holthaus tweeted on January 14th,

There is, right now (as of Jan. 12th), the least area of sea ice on our planet that we’ve ever measured—probably the lowest in millennia.

Holthaus also posted graphs with both the current Arctic sea ice levels and 18,000-year reconstructions.

As the sea ice melts, scientists observe that the ocean gets exposed to more sunlight. Since lower ocean levels are darker than the ice above, the ocean naturally absorbs more heat from the sun. This effect has led some in the meteorological community to fear the melting of a huge ice sheet by Greenland.

Once this ice sheet melts, the waters will flow from the land into the ocean and raise sea levels. Today, Greenland’s ice sheet is 1.9 miles thick. If it melts, it could raise global sea levels by as much as 25 feet.

Future Predictions For Arctic Sea Levels

Although these numbers are sobering, many scientists believe the Arctic numbers will increase over the next few years. After a few years of increase, these numbers will most likely slide down even further. Ed Hawkins, a professor at the University of Reading, said that huge falls like this are often followed by a rebound.

That doesn’t mean, however, that the trend for Arctic ice levels will move upwards. All scientists urge world leaders, especially President Donald Trump, to put global warming policies on the top of their agendas while humanity still has time.

 

Image source: pexels.com/photo/snow-on-sea-photography-196789/

Doctors around the world believe mosquitos injected with a specific bacterium can slow down the transmission of the Zika virus. These modified mosquitos have been released into a few island communities around the world, and most tests have proven successful thus far.

Researchers now want to release bacteria treated mosquitos into larger areas where the Zika virus is prevalent. Although there’s still some controversy over the efficacy of this method, many countries have already authorized the release of these treated mosquitos.

The Science And Success Behind Wolbachia Treated Mosquitos

Scientists are specifically using the Aedes genus of mosquitos in this project. This genus was chosen because it can be found on all continents, excluding Antarctica. Once captured, scientists inject the bacterium Wolbachia into the mosquitos. Research into Wolbachia has shown that once this bacterium is introduced into the Aedes population, it stops viruses like the Zika virus from developing.

Also, Wolbachia helps scientists better control the breeding habits of mosquitos. Male mosquitos with Wolbachia are only able to successfully breed with female mosquitos that also have Wolbachia. Releasing Wolbachia mosquitos into the environment over a long period of time should reduce the number of mosquitos born with viruses like Zika or dengue.

The injected mosquitos were first released as a pilot test in the costal city of Nha Trang, Vietnam. After only a few weeks, the test proved so successful that Eliminate Dengue, a major group behind the Vietnam project, is planning on releasing more mosquitos into Brazil and Columbia. As was reported in the newspaper Xinhua,

The release of mosquitos with Wolbachia…has proven effective.

Xinhua‘s article also said that dengue fever outbreaks went down in Nha Trang after the mosquitos were released.

Another dengue researcher, Professor Zhiyong Xi of Michigan State University, has released Wolbachia mosquitos into the tiny island of Shazai in the southern Chinese megalopolis Guangzhou. On this island, Dr. Xi was able to bring down the mosquito population by an astonishing 96 percent within a month’s time.

While the result is stunning, many scientists wonder whether or not Dr. Xi can replicate his success in a densely populated mainland area. Dr. Xi has said he wants to start introducing Wolbachia mosquitos into more populated regions very soon. His next target will most likely be in Mexico.

Where Wolbachia Mosquitos Will Most Likely Be Released Next

One area of the world that can expect to see Wolbachia mosquitos very soon is New Caledonia. It was announced in December of 2016 that the modified mosquitos will soon be released on this tiny island. Also within the Oceania region, researchers might release mosquitos into Australia and Indonesia. However, there’s no word yet on when these mosquitos will be released.

As for the USA, two states in particular will be receiving these Wolbachia mosquitos soon. Dr. Xi was given permission by the U.S. federal government to release these mosquitos in both Florida and California.

Although all the tests look great, some critics have argued that there could be a few flaws using Wolbachia treated mosquitos in certain parts of the world. A report published by PLOS Pathogens said that the Wolbachia mosquitos don’t work as well at combating the Zika virus in areas where temperatures are extremely high.

The Current Prevalence Of The Zika Virus

The Centers for Disease Control and Prevention (CDC) has released a “Public Health Alert” for places where the Zika virus is active. A few locations on this list include American Samoa, the U.S. Virgin Islands, Puerto Rico, and Miami-Dade County.

There are currently less than 1,000 cases of Zika in the USA. Only time will tell how effective these Wolbachia mosquitos are in more densely populated urban areas after they are released in 2017.

 

Photo by Katja Schulz , available under a Creative Commons Attribution 2.0 Generic license

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Strange circles found around the coastal Namib Desert in southern Africa have baffled researchers for decades. Hundreds of these arid circles, measuring between 7 to 50 feet in diameter, are dotted along the long desert. Two major theories have attempted to explain these so-called “fairy circles” throughout the years, and, interestingly, both may be true.

The Two Major Fairy Circle Theories and Recent Research

Some theorists believe that termites deep beneath the soil form the circles. This group claims the insects clear all the vegetation situated right above their underground nests. Since the soil becomes more permeable without vegetation, rainwater easily flows 50 centimeters below the earth’s surface and into their nests. This, theorists claim, helps form a healthy balance between both the termites and the local environment.

The second main theory behind the Namibian fairy circles is called the water competition theory. As the name suggests, the adepts of this theory believe the fairy circles appear due to intense competition for water between plants.

As long as the vegetation is dense, water levels are maintained and the plants have enough nutrients. However, lonely specimens that do not benefit from the shade of their companions are forced to grow longer roots, extracting water from deep within the soil.

In order to settle this debate, Corina Tarnita, an assistant professor of ecology at Princeton University, decided to look into this matter. She teamed up another Princeton ecology professor, Robert Pringle, to run some intricate computer tests.

They first looked into the termite model using computer models. Their simulation showed that it is very likely various termite colonies establish borders, which would then result in the circular patterns on the desert’s surface. Termite colonies are well known for fighting over territory. Whenever there’s a stalemate, they often form a border.

Both Tarnita and Pringle discovered that every single settlement was surrounded by about six neighboring colonies. This wasn’t only true for the Namibian fairy circles but also correlated to how termites in areas such as Kenya, Arizona, and Mozambique often behave.

Despite these findings, both researchers felt like they hadn’t done the water competition theory enough justice. Tarnita wondered if both theories could actually be right simultaneously.

Tarnita and Pringle ran a computer model that computed for both a large-scale termite pattern and a small-scale pattern resulting from plants fighting over water. They saw a real possibility for both of these theories to be true. Eventually, the researchers headed out to Namibia to see these fairy circles for themselves.

Once the scientists arrived at the Namib Desert, they found the larger circles made by termites, but they also spotted numerous smaller circles that hadn’t been noted before. These smaller circles measured about 20 centimeters in diameter and were roughly 20 centimeters apart from each other. This matched Tarnita and Pringle’s computer model perfectly, and it suggested that both theories could be simultaneously true.

Accepted By Some, Rejected By Others

After Tarnita and Pringle released their data to the world, it received mixed reviews from the scientific community. One of the strongest supporters of the termite theory, Norbert Jürgens of Germany’s University of Hamburg, said that he thought Tarnita’s work helped resolve the debate between termite supporters and water competition supporters. Jürgens now hopes for a “balanced discussion.”

One staunch water competition theorist, however, is not ready to admit both termite and water competition theories can co-exist. Stephan Getzin, who works at the Helmholtz Center for Environmental Research, reported on fairy circles observed in Australia last year. Getzin said that he hasn’t seen any termites in either the Namib Desert or the Australian Outback.

Therefore, Getzin believes

“the termite theory cannot be considered as a strong explanation [of the fairy circles].”

The Theoretical War Isn’t Over Yet

Although Tarnita and Pringle’s research attempted to resolve this issue, the back and forth between staunch supporters of either side will probably go on for some time. Jürgens has already called Getzin’s claim that there are no termites in the Namib Desert ludicrous. After years of work in the field, Jürgens believes termites are always present in areas where these circles appear. Perhaps only further studies will put this fairy circle debate to a close.

Image Source: Wikipedia

Scientists at National Aeronautics and Space Administration (NASA) who are researching Venus are very disappointed to find out that their projects were again not chosen for funding. They had two proposals in the top six, but the agency decided neither one was worth being funded at this time.

The team behind the proposals warned that if NASA does not find a way to fund a project on the planet soon, interest in Venus among scientists will fizzle out.

How Are NASA Projects Chosen?

While most people would assume that NASA gets to decide how they want to spend the money that they get from Congress, it’s actually not the case. The process of getting any funding approved is over two years long.

The procedure begins before March, when the head of NASA (until the 20th of January, this was Charles F. Bolden) asks all of his managers to submit budget proposals for what they will need in two years. NASA operates 10 space centers. The manager of each center must create a budget for their own division.

This is the first time that funding for Venus projects may be declined because the project manager lacks the faith in its importance. Since there haven’t been many exciting developments on Venus lately, the number of people supporting a mission on Venus is diminishing.

By July, the Head of NASA must submit his detailed budget proposal to the Office of the Chief Financial Officer (OCFO). This group of people then makes sure that the submitted plans meet the commitments set by NASA, from the top of the agency to the bottom. The budget then goes back to NASA for a final approval of any changes made by OCFO.

By September, the budget then goes to the Office of Management and Budget(OMB). This office has many smaller committees. In the case of NASA proposals, the budget must be approved by the Science and Space Branch of the Energy, Science, and Water Division.

Up to this point, all people working on the budget are hired permanently. Once the budget reaches the OMB, the budget sees its first political appointee. The committees must present their recommendations to the Director of the OMB. This person is appointed by the President and serves on his cabinet.

Therefore, Venus projects can be turned down at this point because this director doesn’t think that the President would be interested. As you can see, it’s a pretty complicated procedure overall.

What Happens Next? Will We Have a Venus Mission?

After the director makes a decision, this person sends a letter back to the Head of NASA. In in, the director can tell the leader of the agency that he needs to alter how NASA recommends spending money, cancel whole programs or make changes to NASA’s policy.

In this most recent case, NASA asked for funding for six projects. Two of those projects were Venus projects. The committee denied both Venus projects.

Bolton has just one chance to state his case again. Alternatively, he can simply accept what OMB recommends. Once NASA and the OMB agrees, then the final writing of the budget happens to make sure that it looks nice. The plans then go to Congress who must approve the budget. Finally, the president signs the budget.

Robert Grimm, a program director in the space science division of San Antonio based Southwest Research Institute says

With five total missions, and an expectation that two missions were going to be accepted, it seemed natural to do a Venus one and an asteroid one.

But when the process was done, the budget was approved for two asteroid projects, while no Venus proposal was greenlighted.

Conclusion

Getting a Venus project funded is a complicated process involving many different steps. It starts with project managers recommending budgets to NASA’s head. Then, the budget goes to the OCFO who then makes their changes to projects sending it back to NASA’s administrator for his approval.

The budget then goes to the OMB who makes more changes. Finally, the budget goes to Congress for their approval. The final step is for the president to sign the budget. Sadly, considering the recent rejection of the two projects, a Venus mission doesn’t seem to be in stars in the immediate future.

Image source: here.

Scientists are very excited about new lab experiments allowing them to restore eyesight in blind mice. The researchers used stem cells to give these mice the ability to see. This is the first time that they have been able to produce sight where it didn’t exist.

According to the team involved, they do not know if the same procedure would work in people or not, until human trials are completed. If this works out, then blind people may be able to see again as well.

How Did the Researchers Give Sight to Mice?

Researchers working at the RIKEN Center for Developmental Biology, a large research facility in Japan, collected skin cells from the mice. In the lab, they were then able to induce them to make pluripotent stem cells. They were then able to convert these stem cells into retinal tissue. Finally, they transplanted the retina tissue into mice that had end-stage retinal degeneration.

The mice were then put into a test box with two different chambers. They first trained the mice to move from one chamber to the other, using a beep and a light, in order to avoid receiving an electrical shock. Eventually, the beep was eliminated to see if the mice could detect just the light.

In 40 percent of the mice, who had the procedure was done in just one eye, the mice responded to the light. In 45 percent of the mice, where both eyes were transplanted, the mice could see as well. That’s a high percentage for a trial to restore eyesight with no previous groundwork to rely on.

The researchers hope that over time, eye-brain connection techniques can be improved to make these percentages even higher.

Can the Same Thing Happen in Humans?

Lead researcher Dr. Michiko Mandai says:

From a clinical point of view, although we think that these results are very promising, human eyes may have a different environment from mice.

He adds that without human studies, there is no way to know if human eyes would accept such retina transplants and then make connections with the brain. In his opinion, those answers can only be found when human tests are done.
According to the scientists, it would be very exciting if it did work, because this would restore eyesight and light sensitivity to those currently struggling with blindness. They believe that it would also mean those affected could see large objects.

If successful, this would be particularly great news for people with retinal degeneration. While there are several different types of this disease, everyone suffering from it experiences damage to photoreceptor cells (which allow them to sense light). Depending on the stage of degeneration, the person may see a blurred image, distorted, or see no image at all.

The most common type of retinal degeneration is age-related macular degeneration. This disease that is usually seen in people over 50 slowly destroys the ability to see straight ahead. It can eventually make a person go totally blind.

Caucasians are more likely to experience this disease than people from other ethnic groups. Scientists know that over 20 genes that can be passed down can cause age-related macular degeneration.

Therefore, people are at a higher risk if one or both parents have the disease. Those who smoke or do not exercise are also more likely to develop this disease. Eating a well-balanced diet can also help prevent it.

Conclusion

For the first time, scientists have been able to grow retina tissue in the lab from stem cell. They were also able to transplant it into mice and restore eyesight at least partially (in regards to perceiving light). Scientists are still not sure if the same will work in humans or not without completing a human trial.

If the procedure works for human subjects, people with retinal degeneration will be able to see again. This would be great news for everyone suffering from age-related macular degeneration.

Image source: here.

A multinational team of scientists studying gibbons in the Chinese rainforest have discovered a new species. They have named the gibbon Skywalker. This gibbon lives mainly in the high tree tops swinging among the trees.Even though scientists have just discovered this species, they have already placed it on the endangered list.

Hunting, loss of habitat, and illegal trade are sadly the main threats to its existence. Many gibbon species, which also called lesser apes, are highly endangered. Therefore, the team is thrilled to have discovered it, but worried for its future.

What is the Skywalker Gibbon?

The Skywalker gibbon lives at the very top of the trees in the Chinese rainforest in the country’s Yunnan Province. This province is located in the far southwest corner of China. The scientists found this species living in the Gaoligongshan Nature Reserve which is one of the most protected areas in the country.

Despite this fact, the scientists still had to climb to about 8,200 feet up the mountains, because the gibbons continue moving up towards higher areas. They have already lost their habitat to hunting below that level and have no choice but to slowly move upwards.

The whole trip was very demanding on the team, but they were thankful to have the opportunity to study gibbons in their natural environment. Scientists now recognize 13 species of gibbons. The Yunnan Province, where these gibbons live, is very rich in natural resources, and it is precisely the mining which constitutes a threat to their habitat.

The scientists behind the discovery are afraid that the gibbons may face even more problems if miners are allowed into the forest. The mining forces plan on separating the area into smaller segments, which could prove a serious threat to the gibbons’ habitat.

This new species of gibbon lives much higher off the ground than most gibbons in the area. Officially, the gibbon is called the Hoolock tianxing, but the scientists who are all Star Wars fans decided to call it the Skywalker gibbon, as a nickname.

At the moment, the scientists approximate that there may only be 200 Skywalker gibbons alive. They have a different song than any other gibbons previously known, and they have more light colored hair on the top of their heads.

Actor Mark Hamill, who plays Luke Skywalker, is thrilled with the discovery tweeting:

So proud of this! First the Pez dispenser, then the Underoos & U.S. postage stamp… now this!

The scientists were very careful before they announced their finding. They carried out a full physical exam. They also examined this species DNA with other known species before declaring that they had found a new type of gibbon.

Why do Gibbons Sing?

Scientists started to suspect that they found a new species by listening to the gibbons song. Gibbons have very loud songs. The current hypothesis on it is that they use their songs to scare away possible predators, along with attracting potential mates, marking their territory, and strengthening bonds.

It’s also possible that these animals use their singing to tell other gibbons where danger lays. Since their songs will travel a long way, scientists even think that they use their singing to warn neighboring communities.

Previous research noted that gibbons have regional dialects. Therefore, scientists were able to listen in the early morning hours from their camp in the rainforest.

Once they identified the gibbons song, they ran through the mist to catch up with the gibbons. Over time, the scientists started recognizing that they were hearing two different songs.

Conclusion

Scientists are thrilled to have discovered a new species of gibbon in the Gaoligongshan Nature Reserve in Yunnan Province, China. This brings the total number of gibbons to 13. Scientists believe that there are less than 200 of Sky Walker gibbons.

They are very worried that if mining is allowed to separate the reserve into smaller patches, these rare animals that were identified by their song will be even more threatened.

Image source: here.