Evolution

A team of paleontologists find in a new fossil study that the extraordinary regenerative capacities of modern salamanders are likely an ancient feature of four-legged vertebrates that was subsequently lost in the course of evolution.


An evolutionary puzzle in the genome of several different snake species is why their genetic code has DNA that, in most animals, controls the development and growth of limbs. Since snakes have long, legless bodies that such genetic code was likely to have disappeared during evolution but a new study .

Now, they've found an explanation. In a paper  the scientists show that the same genetic tools responsible for limb development also control the formation of external genitalia, and that may help explain why snakes have held on to this limb circuitry through the ages.


In a new study, Nikola-Michael Prpic et al. have identified the driving force behind the evolution of a leg novelty first found in spiders: knees.  

With eight hairy legs and seven joints on each---that's a lot of joints for a spider to coordinate in order to take even a single step. To find some answers, Prpic's research team honed in on a gene called dachshund (dac). The gene was first discovered in fruit flies, and the discoverers named the missing leg segments and shortened legs that result from dac mutant flies after the short-legged dog breed of the same name. 


This spring, the world learned of a newly discovered missing link between microbes and humans called Lokiarchaeota. The actual story is that the microbe Lokiarchaeota, discovered on the deep sea floor by a hydrothermal vent called Loki’s Castle, shares features with both bacteria and us. The spin is that this makes it a missing link between the two.

Researchers ave shown that well-developed eyes come at a surprising cost to other organ systems. 

Researchers have long associated the presence of a well-developed brain with major energy consumption. This means that animals that develop advanced nervous systems require environments where this is possible. There has to be good access to nutrients, and every investment in an organ comes at a cost to some other organ system that is less essential in that particular environment. Up to now, there have been few concrete measurements of how high the cost of a nervous system actually is.

The study involving Mexican cavefish shows that the visual system can require between 5% and 15% of an animal's total energy budget.


Working in a cave complex deep beneath South Africa's Malmani dolomites, an international team of scientists has brought to light an unprecedented trove of hominin fossils -- more than 1,500 well-preserved bones and teeth -- representing the largest, most complete set of such remains found to date in Africa.

The discovery of the fossils, cached in a barely accessible chamber in a subterranean labyrinth not far from Johannesburg, adds a new branch to the human family tree, a creature dubbed Homo naledi.

The remains, scientists believe, could only have been deliberately placed in the cave.


An international team of researchers has sequenced the first complete genome of an Iberian farmer, which is also the first ancient genome from the entire Mediterranean area. This new genome allows to know the distinctive genetic changes of Neolithic migration in Southern Europe which led to the abandonment of the hunter-gatherer way of life.

The study is led by the Institute of Evolutionary Biology, a joint center of the Spanish National Research Council (CSIC) and the Universitat Pompeu Fabra (Barcelona, Spain), in collaboration with the Centre for GeoGenetics in Denmark. The results are published in the Molecular Biology and Evolution journal.


Research into 430,000-year-old fossils collected in northern Spain found that the evolution of the human body's size and shape has gone through four main stages, according to a recent paper. 

A large international research team including Binghamton University anthropologist Rolf Quam studied the body size and shape in the human fossil collection from the site of the Sima de los Huesos in the Sierra de Atapuerca in northern Spain.

Dated to around 430,000 years ago, this site preserves the largest collection of human fossils found to date anywhere in the world. The researchers found that the Atapuerca individuals were relatively tall, with wide, muscular bodies and less brain mass relative to body mass compared to Neanderthals.


New species evolve whenever a lineage splits off into several branches and so a common metaphor for evolution has been to describe evolution as a 'tree of life', where every branch constitutes a species.

But since about 99.999% of all species that have ever existed are already extinct, and we have never even known about them, the tree is more like a bush with things constantly growing and falling off. Last year, a consortium of some hundred researchers reported that the relationship between all major bird clades had been mapped out by analyzing the complete genome of around 50 bird species. This included the exact order in which the various lineages had diverged.


Wolves and foxes are closely related and share many of the same characteristics.

But look at their eyes – where wolves have rounded pupils like humans, foxes instead have a thin vertical line.

But it isn’t just canines –across the animal kingdom, pupils come in all shapes and sizes. So why the differences?

It’s a question that has long interested scientists working on vision and optics. In a new study published in the journal Science Advances, colleagues from Durham, Berkeley and I explain why these pupil shapes have developed.