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Evolution is Just a Theory •Scientific definition of theory: •A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method and repeatedly tested and confirmed through observation and experimentation. As with most (if not all) forms of scientific knowledge, scientific theories are inductive in nature and aim for predictive power and explanatory capability. •The strength of a scientific theory is related to the diversity of phenomena it can explain, and to its elegance and simplicity (Occam's razor). As additional scientific evidence is gathered, a scientific theory may be rejected or modified if it does not fit the new empirical findings- in such circumstances, a more accurate theory is then desired and free of confirmation bias. In certain cases, the less-accurate unmodified scientific theory can still be treated as a theory if it is useful (due to its sheer simplicity) as an approximation under specific conditions (e.g. Newton's laws of motion as an approximation to special relativity at velocities which are small relative to the speed of light). •Scientific theories are testable and make falsifiable predictions. They describe the causal elements responsible for a particular natural phenomenon, and are used to explain and predict aspects of the physical universe or specific areas of inquiry (e.g. electricity, chemistry, astronomy). Scientists use theories as a foundation to gain further scientific knowledge, as well as to accomplish goals such as inventing technology or curing disease. Scientific theories are the most reliable, rigorous, and comprehensive form of scientific knowledge. This is significantly different from the common usage of the word "theory", which implies that something is a conjecture, hypothesis, or guess (i.e., unsubstantiated and speculative).

Evolution is Just a Theory Scientific definition of theory: A scientific theory is a well-substantiated explanation of some aspect of the natural world

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Evolution is Just a Theory • Scientific definition of theory: • A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired

through the scientific method and repeatedly tested and confirmed through observation and experimentation. As with most (if not all) forms of scientific knowledge, scientific theories are inductive in nature and aim for predictive power and explanatory capability.

• The strength of a scientific theory is related to the diversity of phenomena it can explain, and to its elegance and simplicity (Occam's razor). As additional scientific evidence is gathered, a scientific theory may be rejected or modified if it does not fit the new empirical findings- in such circumstances, a more accurate theory is then desired and free of confirmation bias. In certain cases, the less-accurate unmodified scientific theory can still be treated as a theory if it is useful (due to its sheer simplicity) as an approximation under specific conditions (e.g. Newton's laws of motion as an approximation to special relativity at velocities which are small relative to the speed of light).

• Scientific theories are testable and make falsifiable predictions. They describe the causal elements responsible for a particular natural phenomenon, and are used to explain and predict aspects of the physical universe or specific areas of inquiry (e.g. electricity, chemistry, astronomy). Scientists use theories as a foundation to gain further scientific knowledge, as well as to accomplish goals such as inventing technology or curing disease. Scientific theories are the most reliable, rigorous, and comprehensive form of scientific knowledge. This is significantly different from the common usage of the word "theory", which implies that something is a conjecture, hypothesis, or guess (i.e., unsubstantiated and speculative).

This is an image of Neonothopanus gardneri, a bio-luminescent mushroom. Last seen over 170 years ago they have since been rediscovered in a rain forest in Brazil. They

were first described by an English botanist in 1840 after seeing some children playing with glowing material in a small village in central Brazil (Vila de Natividad).

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• Glowing Blue Waves Explained: Pinpricks of light on the shore seem to mirror stars above in an undated picture taken on Vaadhoo Island in the Maldives.

• The biological light, or bioluminescence, in the waves is the product of tiny marine life-forms called phytoplankton—and now scientists think they know how some of these sea beasts create their brilliant blue glow.

• The embryos of tiger sharks fight each other while in their mother's womb; only the strongest one survives for long enough, feeding on it's less fortunate siblings. The young remains within the mothers womb for a year, eating new egg cases as they come down the oviduct. This bizarre pre-birth cannibalism was discovered when a marine biologist found himself bitten as he dissected a pregnant sand tiger shark.

Earth formation in a day

Albino recessive gene expressed

The Pygmy Marmoset is the smallest living monkey – new borns

Damn dirty Apes

Dew covered red veined darter

Some animals have amazing camouflage. Who can spot the Mossy Leaf-tailed Gecko on this tree in Montagne d'Ambre

National Park in Northern Madagascar.

Caught!

This little critter is known as a water bear or a Tardigrade. In 2008, water bears were the first animals demonstrated to be able to survive the vacuum of space. They are virtually indestructible

and can survive being blasted with radiation, intense pressures and years of desiccation. Specimens were launched into space by Swedish scientists and they returned unharmed after

eight days.

• A monster? An alien? Nope, this is a macroscopic image of a Polychaete, or bristle worm. They survive intense sea pressures and live around deep sea vents.

Polychaete worm

Researchers in Indonesia have discovered what looks like a teeny tiny dragon. As yet, we have no information on whether they guard small piles of gold or attack miniature castles.

This was a nesting female found in the Lambsuango Forest reserve and was immediately released after this photograph was taken

Pygmy hippos can grow up to 83cm tall (at the shoulder) and up to 177cm long weighing between 180-275kgs. Unfortunately, due to hunting and

destruction of habitat, there are only around 3,000 pygmy hippos left in the wild in their native habitats in Western Africa.

Color-coded comparative view of bones of the shoulder, upper arm (humerus) in red, the forearm (ulna & radius) in pink, and

wrist (metacarpal) with hand in yellow :

• The Blue Dragon

• This is the Glaucus Atlanticus Sea Slug and it can grow up to 3cm's in length. It is found in tropical and temperate waters and floats upside down on the surface tension of the ocean. Despite being only 3cm's long it feeds on prey often larger than itself, including Man o' War jellyfish, which can grow up to 30cm's.

• Despite the Man o' War being venomous, this isn't a problem for the sea slug. Not only is the sea slug immune to the venom but it actually stores the venom in specialised sacs called cnidosacs. Due to it storing the venom it is actually able to produce a more venomous sting than the Man o' War it feeds on.

• As with most sea slugs, the Glaucus Atlanticus is hermaphroditic, containing both male and female genitalia. Unlike other sea slugs, it mates with their ventral sides facing and both produce a string of eggs.

• I'm sure most of you are aware that in some species of spider the female will devour the male after copulation. But did you know that some males not only do not fight against this cannibalization, they actively promote and facilitate it? The male Redback Spider performs a somersault after mating and literally jumps into the females mouth. But why? What possible evolutionary benefit could there be from enabling your mating partner to eat you?

• Researchers discovered that the environment of these spiders was so hostile that it was highly unlikely that a male would be able to find another mating partner. Therefore it would be better for it to focus on ensuring that the female did not mate again. Mate guarding is a poor tactic for these spiders as the females are so much larger.

• The researchers also found that if a female devoured her first mating partner she was much less likely to accept a second male. If she did not eat her first partner she would usually accept to solicitations of the next male that came along.

The glass frog

Researchers in Madagascar have discovered one of the worlds tiniest lizards. This tiny chameleon

reaches a maximum length of only 29mm.

Close up HD image of the human eye

• This, is the Brazilian Pygmy Gecko (Coleodactylus amazonicus). They range in size between 2 and 4 cm (0.8 to 1.6 inches) but most amazingly, are unsinkable! Despite being vulnerable to rain drops, this gecko has evolved a hydrophobic skin enabling it to to walk, and sit on water.

A video of one in action, courtesy of Life by the BBC here

GFP-tagging in DNA studies

Incomplete dominance is a type of inheritance in which one

allele for a specific trait is not completely dominant over the other

allele. This results in a combined phenotype (expressed physical trait).

For example, if you cross pollinate red and white snapdragon plants, the

dominant allele that produces the red color is not completely dominant

over the recessive allele that produces the white color. The

resulting offspring are pink.

Alternatively you can have co-dominance, when two different

phenotypes are expressed at the same time like in the peacock

pictured.

• Turritopsis nutricula has to be item one on our list of amazing animals for one reason - it is immortal. That isn’t hyperbole – it really is immortal. After reaching sexual maturity, this jellyfish is able to reverse its aging process and become a polyp again. The ability to reverse the life cycle is probably unique in the animal kingdom, and allows the jellyfish to bypass death, rendering the Turritopsis nutricula biologically immortal. Lab tests showed that 100% of specimens reverted to the polyp stage.

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• A golden orb spider successful kills and eats a brown tree snake in Cairns Australia after it gets caught in its web.

• http://www.cairns.com.au/article/2012/04/19/215081_local-news.html

• Titanoboa

• The image is a life size model at the Smithsonian Natural History Museum of the world's largest snake to have ever slithered its way across the Earth. Weighing in at 11,340kg, stretching up to 14.6m and with a body diameter of 1m, it roamed the Earth 65 million years ago. Thankfully, the beast was not venomous, although it could apply up to 2758 kPa (the equivalent of one and a half Brooklyn Bridge's lying on you).

• For more information visit:• ... http://www.huffingtonpost.co.uk/2012/04/03/titanoboa-

cerrejonensis-colombia-smithsonian-the-worlds-largest-snake_n_1398834.html

• Ant mind-controlling fungus

• Research into a fungus found growing in carpenter ants has revealed a dramatic insight into its workings. Infected ants are forced to find and die at spots optimal for the fungus to reproduce. Using transmission-electron and light microscopes, researchers were able to see how the fungus grows inside of an infected ant. The fungus fills the ant's body and head causing muscle atrophy and separating muscle fibres. The fungus can also interfere with the ant's nervous system causing convulsions. This can cause the ant to fall from the trees and into the dense, dark and damp leaf litter floor, ideal conditions for the fungus to reproduce.

• On top of this it was shown that at solar noon (when the sun is at it's strongest), the fungus affects the infected ant's behaviour, forcing it to bite the main vein in the underside of a leaf. It then detaches the muscles associated with the opening and closing of the jaw leaving the jaw locked in position around the vein. A few days later, a stroma (the fruiting body of the fungus) grows through the ant's head and spreads spores, able to be picked up by any other passing ant.

• Synthetic DNA shown to evolve

• Scientists from the UK Medical Research Council's Laboratory of Molecular Biology have developed polymerases for artificial DNA, which not only "unzips" the artificial DNA, but manages to transcribe the genetic code to natural DNA, and back again.

• This hints that if there is life beyond Earth, it could be bound to evolution if not the same chemistry for life here. It also shows that life may not solely be restricted to DNA or RNA.

• It should be pointed out that this does not represent a full genetics platform (as it's still dependent on DNA), and that a self replicating system which does not require DNA still needs to be developed.

• This research has implications in many fields, including astrobiology, synthetic genetics and the search into the origins of life (DNA/RNA). It is believed that DNA evolved from RNA, but that RNA in turn evolved from a simpler molecule that performed the same function.

• http://www.nature.com/nchem/journal/v4/n3/abs/nchem.1241.html (Subscription)• http://www.sciencemag.org/content/336/6079/307.summary (Subscription)• http://www.bbc.co.uk/news/science-environment-17769529 (Free, Journalist)

• Turn that frown upside down.

• May I introduce to you, the rosy-lipped batfish (Ogcocephalus porrectus). A close relative to the red-lipped batfish, it can be found crawling along the sea floor off the coast of Costa Rica. Not being very good swimmers they "get about" by walking on their fins.

• So next time you're swimming of the coast of Costa Rica, keep an eye out for one of these beauties

• Bees beat supercomputer

• Bees have been known to be good at facial recognition, but thanks to a new study (2010) they have been shown to out think a supercomputer too. The "travelling salesman" is a problem put to supercomputers that often takes days to solve. It involves trying to find the shortest route between cities, whilst only visiting each city once.

• This was put to the bees in the form of artificial flowers. With flying requiring a lot of energy bees discover the shortest route between flowers extremely quickly, and when new artificial flowers were added in the study, the bees quickly discovered the shortest route using the angles of sunlight. The study was designed to see if the bees would visit the flowers in order of discovery, or via the shortest route possible (to visit all flowers). Bees are the first animal to have figured this out, according to researchers at the Queen Mary University of London.

• So it would seem size isn't important, when it comes to intelligence