Dengue: The Neglected, Neglected Tropical Disease

6 May, 2013 by

Modern medicine can boast a number of triumphs against infectious disease over the past century; Smallpox killed around 500 million people in the 20th Century before its eradication in 1979 as a result of vaccination. The Global Polio Eradication Initiative began in 1988 and has achieved considerable success, with eradication complete in the Americas, Europe, the Indo-West Pacific and China. Last year, only 223 cases of Polio were reported globally. It comes as no surprise that those diseases against which we have had the greatest success are those that affect developed nations. Increasing attention is now being paid to the many debilitating and often deadly infectious diseases, which continue to affect billions of people in developing nations; a category of diseases known as NTDS (neglected tropical diseases).
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Selfish Strategies in Cooperative Society

10 March, 2013 by

Social insects show extraordinarily high levels of cooperation, giving up their reproductive opportunities and even sacrificing their own lives to save the colony. The social insect colony is a well-oiled machine, each part has its own key role to play, together forming an intelligent and adaptive society. Most people are familiar with the highly advanced social insects, such as honeybees and leaf cutter ants. Their societies are huge and intricate, and we have gained many fascinating insights from them. However, they tell us very little about how these societies evolved, or what it meant to be cooperative in a more primitive sense.

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The Magic of Medicine: Gene Therapy

7 February, 2013 by

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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The Curious Case of Turritopsis

6 January, 2013 by

The Immortal Jellyfish

The idea of ageing backwards might seem like the kind of far-fetched tale that only the likes of Brad Pitt could sell, but for some of our distant, under-water cousins, it’s just a really bad day. A few unusual jellyfish species have evolved the ability to completely rearrange the cells in their bodies and return to an earlier life stage. They use this curious talent to deal with times of stress; if adult jellyfish (medusa) find themselves in unfavourable conditions, they can simple revert to their juvenile form and wait it out until things improve. Scientists believe this may enable them to endure poor environments and ultimately spread across the globe into regions other jellyfish cannot reach.

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Novum Manu

25 November, 2012 by

The Science of Artificial Hands

Our hands are possibly our most versatile tool; we use them for almost every aspect of our daily lives and few of us could imagine surviving without them. For those unlucky enough to suffer from congenital hand malformations, or amputees as a result of disease or injury, this is even more clear. In the US, over 40,000 people have undergone hand or arm amputation, most commonly due to injury, cancer or vascular complications of diseases such as diabetes. Although limb loss may once have been a truly debilitating and lifetime loss, remarkable advances in artificial limb technology are making the outlook for amputees much better.

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Animal Personality Part II:
The Evolution of Personality

18 November, 2012 by

The field of research into personality and behavioural syndromes in animals has blossomed over the past few decades. With ample evidence for it’s existence, biologists have begun to consider its evolution; what is the adaptive benefit of personality? How are multiple personality types maintained in a population? Why do personalities exist when they sometimes result in maladaptive responses?

All these questions, and any evolutionary questions we might care to ask, make the assumption that personality is heritable. Without heritability, personality cannot be passed from generation to generation, and cannot be subject to natural selection. There is now plenty of evidence for high heritability of many personality traits in animals, although there is also an important influence of the environment too. Heritabilities estimates vary, from 0.22 – 0.61 in wild great tits, 0.32 in social spiders, 0.54 – 0.66 in humans and 0.2 – 0.8 in dumpling squid. These genetic influences may in part be reflected in brain morphology; one study in humans found differences in brain structure relating to neuroticism, conscientiousness, and extraversion. More neurotic people have a smaller total brain volume and a smaller frontotemporal surface area, whilst extraverts have a thinner inferior frontal gyrus.

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Animal Personality Part I:
Individual Differences

4 November, 2012 by

To even the most casual observer, it is clear that people are not homogenous in their behaviour, and that this goes beyond possible nurture influences such as cultural upbringing. Individuals vary in their behaviour in a consistent manner; some people are generally more aggressive, friendly and adventurous in every aspect of their lives. So obvious is this observation that we even have a word for it – personality. Likewise, anyone who has spent any significant amount of time in the company of animals will almost certainly acknowledge that they are not all the same. The extent to which this is apparent varies from species to species, of course, but the observation is not a revolutionary one. And yet, until relatively recently the concept of ‘personality’ in non-human animals was revolutionary. And it has had to work hard to shake off the criticism of anthropomorphism and pseudoscience.

It was long assumed that animals were infinitely plastic in their behaviour, being able to respond adaptively to all environments. When people actually started to look, however, it became apparent that this wasn’t the case. Individuals showed substantial variation in their responses to certain events and environments, and these responses were not always adaptive. There was a strong correlation however, in the responses of a single individual over time. Personality, you say?

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What Else Makes Us Human?
Fire

14 October, 2012 by

Over the last few months I’ve been discussing the characteristics that make us human, and which of the classic ‘uniquely human’ traits, really are ours and ours alone. But one aspect of human behaviour which I have not discussed so far is our use of fire. No other animal has learned to harness and control fire as humans have.

A recent discovery of wood ash along with animal bones and stone tools in a cave in South Africa suggests that humans may have used fire as early as 1 million years ago. This is around 300,000 years earlier than previously thought, and may indicate that earlier hominid species such as Homo erectus were using fire. Other tentative support for fire use by early hominids such as H.erectus and A.robustus have been found in South Africa and Kenya, possibly as early as 1.5 million years ago. Further evidence from Northern Israel in the form of burnt flint tools and plant remains indicates that H. erectusmay have been controlling fire around 800,000 years ago.

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The Social World of Slime

7 October, 2012 by

Social behaviour in animals is not uncommon, and we are rarely surprised to observe cooperation in nature. However, most explanations for cooperative behaviour rely upon a certain level of cognitive ability. Cooperating willy-nilly leaves individuals open to cheaters, so successful and long-term cooperation between individuals often relies upon individual recognition. Many social groups are composed of relatives. This makes a lot of sense, as helping relatives yields benefits without the need for reciprocation in the future, because relatives share genes. But still, you might expect that even this requires basic intelligence – you need to be able to recognise who are your relatives.

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