Shy Hermit Crabs Have More Luck with the Ladies

Nice guys finish last? Not for the hermit crab – shy males produce more sperm and are more successful with the ladies.

While we accept the individual differences in behaviour between humans without question, terming it ‘personality’, the idea personality in animals has been met with great scepticism. However, evidence for consistent behavioural differences between individuals, known as personality or behavioural syndromes, is now widespread, the question remaining is why? What is the benefit of personality? Some scientists suggest that different personalities represent different life strategies relating to risk taking and investing in the future, others suggest that personalities exist because environmental conditions are variable and different strategies fair better under different conditions.
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Immaculate Conception: Clonal Reproduction in Snakes
(and other animals)

Reproduction takes two, right? Well, not always. Many arthropods and microscopic animals called rotifers reproduce clonally and although it is relatively rare in vertebrates, clonal reproduction has been confirmed in several species of fish, amphibians, birds and reptiles. Known as parthenogenesis, clonal reproduction in vertebrates can occur when an offspring develops from an unfertilised egg. Parthenogenesis has never been observed to occur naturally in mammals, although it is possible to induce it artificially in the lab.
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Alternative Medicine II – Body Manipulation: Osteopathy and Chiropractic Care

Probably one of the most widely used and trusted of the alternative medicines are manipulative therapies such as osteopathic and chiropractic interventions. More than 30,000 people visit an osteopath every day, with complaints ranging from back and neck pain to headaches and even asthma. Both practices come with an expensive qualification and official licensing, and many people I have spoken to have simply assumed that these treatments are part of the scientifically proven body of treatments we know as ‘modern medicine’. But both chiropractors and osteopaths in fact practise alternative medicine.
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How Much Would a Mole of Moles Weigh?

Question:

How much would a mole of moles weigh? (asked by Anonymous)

Answer:

There are two ways to interpret this question, both of which are equally silly. Maybe you mean a mole (unit of measurement) of moles (the subterranean mammal), or perhaps you mean, how much would a mole of mole molecules weigh? I’ll deal with each possibility in turn.

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Recoding Genes: How Post-Transcriptional Editing is Giving Squid the Upper Hand

Natural selection is incredibly good at adapting organisms to their environment, even those environments that are harsh and difficult to live in. But the changes currently happening to the World’s climate, hydrology and land-use may be too rapid for natural selection to act, in most cases. For some species, natural selection has provided the tools to adapt more rapidly, through behavioural or physiological changes. A few species have gone further still, evolving the ability to edit their own genes as they are expressed. Recent research shows this ability is used rampantly by certain species of squid, which may explain why they have responded relatively well to human impacts on the environment so far.
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Which is slimier?

Question:

Is a Slug Slimier than a Snail? (asked by Anonymous)

Answer:

Land snails and slugs like the ones you get in your garden are members of the class Gastropoda, along with sea snails, sea slugs and limpets. However, they do not represent distinct branches of the evolutionary tree – slugs are just species of snail that have lost their shell. There are even some snails that have a reduced shell – halfway between slug and snail. So this makes it difficult to answer the question.

However, there are some good reasons why slugs (shell-less snails) might seem to be slimier than their shelled counterparts.

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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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Sloths Move Slow, Evolve Fast

Sloths might be notorious for their leisurely pace of life, but research published last year shows they are no slow coaches when it comes to evolution.

Sloths, as we know and love them, are small, slow-moving creatures found in the trees of tropical rainforests. But modern sloths are pretty odd compared to their extinct relatives. Sloths (Folivora) are represented today by just six species in two families; the Megalonychidae (two-toed sloths) and the Bradypodidae (three-toed sloths). But 20,000 years ago there were perhaps as many as 50 species of sloth spread across the globe, and most were relatively large, ground-dwelling animals quite unlike modern sloths. While most modern sloths weigh in at a modest 6kg, extinct species such as Megatherium americanum and Eremotherium eomigrans could weigh up to 5 tonnes!

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Alternative Medicine I – The Ultimate Dilute: Homeopathy

Homeopathy. One of the most popular alternative medicines in the Western world, and perhaps the most widely misunderstood. The science against homeopathy, like the skeptics, is unequivocal. The British Homeopathic association list homeopathy as a possible treatment for long-term chronic problems such as eczema, chronic fatigue syndrome, asthma, migraine, IBS and depression, but numerous healthcare bodies agree there is no evidence that homeopathy is effective in treating any health condition.

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