Human-like features of the feet and gait were in existence almost two million years earlier than previously thought, according to recent analysis of ancient footprints in Laetoli, Tanzania.

Earlier studies suggested that the characteristics of the human foot, like the ability to push off the ground with the big toe and a fully upright bipedal gait, emerged in early Homo approximately 1.9 million years-ago but researchers now say that footprints of a human ancestor dating back 3.7 million years ago show features of the foot with more similarities to the gait of modern humans than with the type of bipedal walking used by chimpanzees, orangutans and gorillas.

Between Easter’s religious reminders and a molecular evolution class overdose of population genetics, I shouldn’t have been surprised to wake up yesterday from an unsettling dream about taking my midterm exam on Noah’s Ark. The ocean was rising, Noah was hustling animals aboard, and I was battling asthma (thanks, furry animal allergies). But what bothered me most about all this wasn’t that I’d forgotten the formula for heterozygosity. It was that there were only two animals of every kind.

Religious beliefs aside, today’s scientific consensus is that you need more than two individuals to save a species.

Sex is costly. Yet it is widespread throughout the animal kingdom, so there must be some advantages to it. And still, it seems easier to list disadvantages. Sexual reproduction is complicated, requires more time and uses more energy than its asexual counterpart. Partners have to find each other and coordinate their activities to produce the next generation. Another problem is the so-called ‘cost of meiosis’, meaning that, in sexual reproduction, only half of the genome is passed on. Compared to an asexually producing individual which passes on its entire genome, this is a high cost indeed. Another cost is the production of males that will not all succeed in reproducing, and thus waste resources.

Botany: A Blooming History

And now we return to part one of this series

The term sperm competition can be used in two ways.

In the broad sense, it involves a large range of morphological, behavioural and physiological attributes, including courtship and copulation behavior (for example, a male that guards females to ensure that he’s the father).  

In the narrow sense, which is the focus of this article, sperm competition is used to denote the physiological processes occurring inside the female’s genital organs after multiple matings.

(For a brief review on the complexity of sperm selection, see Wigby and Chapman, 2004).

The world is changing. Climate change, deforestation, and much more, are all having an impact on our litlle planet. A question that follows this statement quite naturally, is 'Will the earth's organisms be able to adapt to the changing circumstances?'

Well, probably, some will, given enough time. But that might be a problem.

The world is changing fast. So the question should really be 'Will the earth's organisms be able to adapt to the changing circumstances fast enough?' 

Recently, research has been conducted to see if certain life-history traits could be correlated with DNA mutation rates. By using whole-genome sequence data for 32 species of mammal, the researchers tested the hypothesis that DNA mutation rates are influenced by species-specific life-history traits. These mutation rates were estimated by looking at the rate of substitutions of neutrally evolving DNA segments. 

This type of research could make it possible to infer life-history information of extinct species, providing that genomic data is present.

The research focused on three life-history traits.

1) Generation time

When I was a teenager, my two scientific passions were astronomy and botany.  However, at my school in the early 1960s, one could either do A-levels in Mathematics - Physics - Chemistry (Science A) or Chemistry – Botany - Zoology (Science B).  I chose the former option, being very much put off by medicine which was more or less entailed with the latter.  Botany still is a scientific passion – if I were time-transported back to the Jurassic I would be eager to investigate the flora, leaving others of the party to keep a watch-out for dinosaurs.

What's ailing biology?

Wilson da Silva, Editor-in-Chief of COSMOS, a science publication in Australia, was attending a lecture by Freeman Dyson lecture at the Perimeter Institute in Canada when Dyson said, "It's sad but true that most discoveries in biology are made by physicists."