Tibetans evolved to cope with UV

Study identifies seven new loci associated with high-altitude living

Tibetan populations have evolved at least nine specific genetic variants to help them survive the extreme conditions of the Tibetan Plateau. Living permanently at over 4,000 m above sea level, these populations have been coping for millennia with 40% less oxygen and 30% stronger UV radiation, as well as exposure and limited food.

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Evolving the Modern Dinosaur

There are more than 10,000 species of living, breathing dinosaurs on Earth today. It’s just that we call them birds. And while a chicken might seem like a measly ancestor for the enormous T-rex, modern birds can teach us a lot about dinosaur evolution. A huge genome sequencing project, which recently culminated in the publication of nearly 50 genome sequences and the most accurate tree of bird evolution to date, has further blurred the line between bird and dinosaur. Spurring a plethora of studies into the origins of our modern feathered, singing friends, the December 2014 edition of Science taught us that the transition from dinosaurs to birds was gradual and began long before the Dinosaurs were gone. It taught us that it involved multiple independent origins of bird song, a characteristic that now dominates around 10% of the genome. And it taught us that the evolution of flight was facilitated by new genes and new gene regulation, but also by the loss of genes.

Making a Chicken from a T-Rex

Last October, the Therapod Working Group constructed a new phylogeny (family tree) for Dinosaurs, based on morphological characteristics measured in fossil remains of over 150 different species. The new tree revealed fascinating insights into the nature and pace of avian evolution.

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The Genetics of Sleep

Every night’s sleep is different, and how you sleep on any given night is likely to be determined largely by short-term causes – what and when you ate, how much exercise you did today, stress levels, what you watched on TV, whether your partner is snoring – but there are also fundamental, long-term differences between people in their sleep patterns. It is thought these differences are often genetic, and recent research supports this idea, identifying for the first time a gene involved in determining how much sleep we need.

Sleep is a huge part of our lives, and the lives of many animals. Although we still do not fully understand the strange phenomenon that takes up a third of our lives, it is clear that without it we cannot survive. But with a growing number of things keeping us awake – work, tv, friends, sport, buzzfeed, reddit – how much sleep is enough sleep?

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A New Language for Life

All the beautiful, remarkable complexities of life that we see around us are, believe it or not, encoded at the most basic level by an alphabet just 5 letters long. The DNA code, which is shared by all life on Earth, is formed from molecules known as nucleotides which come in just four forms: Adenine, Cytosine, Guanine and Thymine. RNA, the single-stranded cousin of DNA which is important in translating DNA into protein, adds a fifth letter – Uracil. It is truly one of the most impressive feats of evolution, that such a simple alphabet can generate such diversity and adaptation. However, recently scientists from The Scripps Research Institute, California have engineered a life form with an expanded vocabulary.

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The Magic of Medicine: Gene Therapy

In the 60 years since Watson and Crick’s landmark discovery of the structure of DNA, our understanding of how genes influence disease has increased exponentially. For some conditions, an exciting therapeutic prospect exists: gene therapy. Gene therapy attempts to repair faulty genes instead of simply treating symptoms.

For many conditions, the exact genetic mechanisms underlying them have now been elucidated. While a lot of diseases are the result of a complex interaction between multiple genes and environmental factors, others are the result of a single mutation, resulting in the failure to produce an essential functional protein. For such conditions, an exciting therapeutic prospect exists: gene therapy. In principle, the idea behind gene therapy is very simple. Whereas conventional medicine generally attempts to replace the missing gene product or repair the damage caused by its absence, gene therapy attempts to repair the faulty gene itself. Why treat symptoms when you can treat the cause?

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What Else Makes Us Human?
Drug Use in the Animal Kingdom

Whilst writing the series on “What Makes Us Human?”, I started thinking about less obvious, less traditional ideas of what traits are truly human, and human alone. One characteristic occurred to me that seemed obviously to be unique to humans: recreational drug use. It seemed implausible that animals in the wild were indulging in drug abuse purely for their own entertainment, and I wondered if this could give some perspective on what it means to be human. But, as it turns out, I was wrong.

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Eye Colour Genetics: A Window Into The Soul

In literature, television and film, the eyes are often imbued special meaning; the idea that you can tell something about a person, or what they are thinking or feeling, by gazing into their eyes. Eye colour is often considered a very straight-forward trait, with eyes being either brown, blue or green. But it is easily apparent that there is far more variation in human eye colour than that allows for, and that its inheritance is not always what one might expect. There are even some people out there who will try to convince you that your eye colour is controlled by diet. What really controls the appearance of our eyes? What are our eyes saying about us?

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Reasons Why Evolution is True Part VIII:
PreCambrian Rabbits

The fossil record is one of the most obvious pieces of evidence for evolution. Fossils have been known since human history began, and Aristotle first noted the similarity between fossils and living animals, leading him to conclude that fossils represented deceased creatures, a view supported by Leonardo da Vinci. By the 19th century, people were increasingly beginning to appreciate that some fossils represented extinct animals, and that their positioning in the rocks appeared to represent that passage of time. Now there is also ample evidence from molecular genetics and radiometric dating that the fossil record does represent the evolutionary history of life on Earth. Despite this, creationists still continue to argue otherwise. Some have suggested that the fossil record represents animals killed during one or more biblical floods, however this is incongruent with the evidence available.

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