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Crocodile Eyes are Designed for Lurking and Hunting

Crocodile eyes are watching you. The thought of being stalked by a crocodile is enough to make anyone sweat profusely. In some parts of the world nipping to the waters edge for a quick drink is not good advice. Crocodiles aren’t just scary to most people simply because they have huge teeth and a fierce bite, though. Crocodiles lurk and pounce on their prey in a violent attack appears to come from out of the blue. The crocs you see will lurk just beneath the water, with only their devious mean looking eyes keeping a lookout for something delicious — like one of us for example.

In a recent study it has been shown that a crocs eyesight is pretty decent indeed. The new research shows that, while a crocodile may not have as good eyesight as you or I for example, it’s vision is well adapted for craftily lying in wait at the water’s surface for the perfect moment to strike and lunge at it’s unsuspecting prey.

Crocodile Eyes are Designed for Lurking and Hunting

Nicolas Nagloo and his academic colleagues from the University of Western Australia in Crawley recently investigated the eyes that were taken from three young saltwater crocodiles and also two young freshwater crocodiles.

“Both Australian species of crocodile possess a bright yellow iris, a slit pupil and a relatively large lens,” the team notes. Such features in the crocodiles eyes, that were known before this study, are useful for seeing prey and other objects in low light. (The animals, though, don’t have great vision underwater.) Crocodiles also possess a “mobile slit retina” which assists the crocs in controlling just how much light reaches the eye during the day time.

A study of the cells and dissections of the crocodile eyes revealed three types of single cones. This suggest that the crocodiles can see colors in their field of vision pretty well. However the freshwater crocs appear to be a bit more sensitive to the color red than their saltwater cousins. These crocs which are known as salties in Australia may help the freshies see better in streams and rivers.

Each species of crocodile further have a horizontal streak of high spatial acuity. This acuity is what enables the crocs to search for their prey without ever having to move their heads. Meaning that they do not have to make any movement that might give the game away.

That the two species of crocodile have eyes that are so strikingly  similar is somewhat interesting given that these are crocodiles and reptiles separated by some 12 million years of independent evolution. They live in different habitats and prefer to hunt for different prey. for example the freshwater crocs prefer smaller animals and more marine life. Yet each species of crocodile have developed a similar style of hunting their prey.

A style in which the crocs lurk menacingly just beneath the water line and scan the immediate surroundings for a suitable tasty meal. The crocodiles, this research demonstrates have eyes that are specialized to aid in such attacks. Beware the next time you head down to the waters edge. You never know what might be there just under the surface of the water.

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Heavy Rain Can Trigger Earthquakes

Earthquakes are an unpleasant fact of life, they occur worldwide and there are several quakes, some serious each year. Most quakes occur with an ocean floor epicenter, some will occur across land in proximity to population centers and with differing levels of severity. Where it rains, it apparently rumbles underground. New research in New Zealand suggests that intense rainwater and melting snow actually encourage earthquakes along a New Zealand tectonic fault known as the Alpine Fault.

If this is proven to be true then it establishes a link between heavy rainfall and the likelihood of earthquake or tremor as the ground moves.

Heavy Rain Can Help Trigger Earthquakes

New Zealand’s Alpine Fault water flow shows that more than 99 percent of the water flowing through the New Zealand Alpine Fault fault came from direct rainfall, as reported by researchers in the April 19 edition of  Earth and Planetary Science Letters. Previously scientists were always aware that that underground fluids help trigger quakes. Yet in many cases it was never clear where these underground waters actually came from. For example these fluids could originate from lakes, rivers, underground caves or rainwater. The possibilities as to the origin of these waters were always varied.

In this case in New Zealand, the nearby Southern Alps direct heavy rainfall and melting snow on top of the Alpine Fault. Within the fault the water is trapped and it permeates into the ground. The fault “essentially [is] promoting its own large fluid pressures that can lead to earthquakes,” says study coauthor and academic Catriona Menzies, a researcher and geologist at the University of Southampton in England.

Identifying source of all this flowing water into the fault will help scientists better predict the fault’s seismic cycle, she says. This could be a powerful tool in predicting earthquakes in other areas of the world and in protecting valuable cities and their population; cities such as San Francisco which lives under the constant threat of serious earthquake.

New Zealand of course is a country that sits on the boundary where the Australian and Pacific tectonic plates collide. As the plates move against each other the collision of energy and friction generates a powerful earthquake along the Alpine Fault. The quake hits here around once every 330 years. The most recent serious quake caused by the Alpine Fault in New Zealand was in 1717. This plate movement also gradually formed the Southern Alps as the two tectonic plates forced the landmass upward.

It is here that moist air condenses when rising over the mountains, which causes heavy rainfall that typically exceeds 10 meters each year. The researchers Menzies and colleagues naturally pondered on just how much rainwater enters the Alpine Fault zone. Fluids within a fault help encourage quakes by altering the composition of rock and soil and by interfering with the natural forces that hold two sides of a fault together. In essence the rainwater destabilizes the rock within the fault lines making it more prone to movement and therefore generate a resulting earthquake or tremor.

 

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Astronomers say that three potentially Earth like and habitable planets orbiting another star have been discovered using the technique that detects wobbles in light. In this instance the three planets are orbiting an ultra cool dwarf star much smaller than our own sun. The trio of new worlds are located about 39 light years from Earth. Their exciting discovery have opened up a new “hunting ground” in the search for alien life outside our home solar system.

The trio of Earth-like planets are very similar in size to our home planet of Earth. Each of these new worlds are close enough for their atmospheres to be analysed with existing technology we already have, scientists said. Furthermore their relatively close distance to our home world, although a prohibitive distance for travel with current technology means that they are close enough for future generations of space explorers to reach.

Perhaps within several generations. In other words future exploration by mankind maybe feasible if reasonable advances in technology come to pass and certain assumptions about human capability are met.

“This is the first opportunity to find chemical traces of life outside our solar system,” Michael Gillon, an astrophysicist at the University of Liege in Belgium, said.

How the Trio of New Worlds Were Discovered

Using a unique 60cm telescope based in Chile, the telescope is known as TRAPPIST, scientists and astronomers tracked several dozen dwarf stars not visible with optical ground based telescopes.

The telescope works by identifying the most promising candidate star. In this case the star is about one-eight of the size of the Sun. The next phase in the discovery programme is to observe the star for several months. After this time had elapsed scientists noticed its infrared signal faded or dipped slightly at regular intervals. This light phasing and dipping is a process of discovery that suggests it had local objects orbiting it such as planets.

The astronomical study concluded the size of these worlds and their proximity to the star. This gathered data meant all three planets could have surface regions at temperatures within a range suitable for sustaining liquid water and life. For example in the temperature range of Earth and Venus. More data will likely become known as these trio of new worlds garner focussed attention in the coming months and years.

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Come out from under that rock, human, because soon we’ll be moving to Mars! Well, not just yet, bu SpaceX have announced their hopes of launching an unmanned Dragon capsule to Mars on a private mission in 2018. They will then become the very first private company to have landed on another planet.

And on that note, NASA has decided to hitch a ride on SpaceX’s successful bandwagon, and of course, share the spotlight. So NASA Deputy Administrator Dava Newman announced in a blog post that NASA has “accepted” partnership with SpaceX on their mission; NASA agreed to provide technical support to SpaceX’s mission. And in return, NASA expect SpaceX to provide them with data about the spacecraft’s entry into the planet’s atmosphere, its descent, and its landing. NASA’s agreement with SpaceX is completely free, depending solely on an exchange of data. So technically, Nasa’s using SpaceX for their landing strategy which is a very smart move, saves them millions financially, and gets them a “partnership”, as well!

On the other hand, NASA just cut the funding on its own Mars landing mission by up to 85%. Their mission starred a giant doughnut-like inflatable spacecraft with low density and supersonic deceleration and uses parachutes and Mar’s atmospheric friction to land. However, last year’s test didn’t go too well and the project was costing them about $ 2 million per year. Hence, they announced that the program cut was due to budget constraints.

NASA’s past “partnerships” with private companies have resulted in startling successes so far. And on top of that, they are getting cargo delivered to the ISS for almost no cost on their part! So good going, NASA, you’re one smart and opportunistic cookie!

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Science is hope. I believe that whole-heartedly. After all, this discovery alone gives tons of hope to several human beings out there. Do not give hope! If single-celled organisms displayed some form of intelligence, then there’s definitely yet hope for you!

According to Science Daily, a group of scientists recently decided to test out the learning abilities of a simple organism, the protist, or slime mold, and they were fascinated by the outcome. Turns out, it exhibits of form of learning known as habituation. So the scientists at the Centre de Recherches sur la Cognition Animal at the Universite Toulouse III, exposed 4 groups of slime mold to different situations, sort of like an obstacle course. The slime mold was surprisingly endowed with some amazing learning skills, such as solving a maze, avoiding traps, and optimizing nutrition.

So the four slime mold groups were exposed to a 9-day challenge that included obstacles from difficult but harmless substances to pass in order to reach their food. Two groups were confronted by a bridge with quinine, one group was confronted with caffeine, and the last was the control group. At first, the three groups seemed hesitant to pass through the substance; however, they gradually learned that the substance was harmless and by day 6, they were passing the substance as fast as the control group. This, according to the scientists, is habituation. Then, after 2 days without contact with the obstacle they returned to the initial state of distrust. Furthermore, the habituation of the slime mold was substance specific; meaning, the slime mold that was habituated to caffeine showed distrust to quinine, and vice versa.

This form of learning exists in all animals, but it is the first time that it is observed in non-neural organisms. Learning and memory are key skills for every animal to survive in a fluctuating and often dangerous environment. However, prior to this study, any learning skills were associated with organisms that were endowed with a brain and a nervous system. This discovery will help scientists shed some life on the origins of learning, in the times billions of years ago, when we also were brainless. Furthermore, it will help scientists figure out whether other single-celled organisms, such as viruses and bacteria, also possess the same learning ability.

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This year has witnessed one breakthrough discovery after the next when it comes to finding cures and treatments for lethal diseases. And while HIV is no longer a death sentence – and this is by no means a breakthrough discovery – yet a truly reliable treatment has yet to be found. In a recent study published in the journal Nature, American and German researchers tested a new preventive treatment on macaque monkeys. The results showed a delay in HIV infection of up to 6 months!

The researchers split the macaques into 4 groups, injecting each with a different anti-body. The results were an average delay of 12 to 14 weeks, and some even remained protected for as long as 23 weeks. However, the monkeys that were not injected with anti-bodies were infected in an average of 3 weeks. Now this is not a breakthrough discovery as anti-bodies have been previously tested out on monkeys for HIV prevention. But in the old studies, a single high-dose of the virus was good enough to break the protection and get the monkey infected. Furthermore, HIV preventive medications already exist. For instance, PrEP pills help reduce infection risk to over 90%! However, today there are 37 million people in the world infected with HIV, and in 2014 alone, around 2 million got newly infected. That is not due to the lack of efficiency of the PrEP pills, for example, but due to the fact that the pills needs to be taken daily; most people forget to take them or only take them before sex, and this reduces the drug’s efficiency.

For years now, scientists have been trying to find an HIV vaccine as this is the ideal solution. However, so far it has proven highly difficult if not impossible to produce such a vaccine. Moreover, anti-bodies seem to be a much better option, as instead of giving the body the disease itself, scientists give it the anti-bodies it needs to fight off HIV, which saves it time, energy, and effort to produce them itself. Furthermore, the results of the monkey trials are positive, as the anti-bodies would be even more effective on humans. However, some scientists have wondered why the researchers didn’t use a cocktail of anti-bodies which would’ve made the treatment more effective. After all, exposing the virus to one anti-body makes it quite easy for it to grow resistant, which it does and quickly. But injecting the body with a cocktail would decrease the chance of immunization-resistant viruses. Still, the researchers say they wanted to figure out how effective each of the anti-bodies was individually, before attempting to mix them up for better results.

The first clinical trials of the anti-body VRC01 will start soon in Peru, Brazil, and the US. The trials will enroll 2,700 people with high-risk of being infected to test how well the anti-body protects them from infection. Later on this spring, the trials will also start in different African countries.