Evolution

The genome sequence of a 24,000-year-old Siberian individual demonstrates genomic signatures that are basal to present-day western Eurasians and close to modern Native Americans and provides a key piece of the puzzle in the quest for Native American origins and also sheds light on the genetic landscape of Eurasia 24,000 years ago. 


Everyone has a hypothesis about the 'birthplace of life' and a new paper adds clay to that list.

In simulated ancient seawater, clay forms a hydrogel, a mass of microscopic spaces capable of soaking up liquids like a sponge. Over billions of years, chemicals confined in those spaces could have carried out the complex reactions that formed proteins, DNA and eventually all the machinery that makes a living cell work.

Clay hydrogels could have confined and protected those chemical processes until the membrane that surrounds living cells developed, according to the computer model.


A new paper in Cell Reports finds that it doesn't take a lot of genetic changes to spur the evolution of new species—even if the original populations are still in contact and exchanging genes.

Once evolutionary divergence happens, though, it evolves rapidly, ultimately leading to fully genetically isolated species.

To reveal genetic differences critical for speciation,the researchers analyzed the genomes of two closely related butterfly species, Heliconius cydno and H. pachinus, which only recently diverged. Occupying similar ecological habitats and able to interbreed, these butterfly species still undergo a small amount of genetic exchange.


A new collection featuring research on the complex evolutionary cascade theory that made the unique gigantism of sauropod dinosaurs possible has now been published in PLOS ONE.

Sauropod dinosaurs were the largest terrestrial animals to roam the Earth, exceeding all other land-dwelling vertebrates in both mean and maximal body size. While convergently evolving many features seen in large terrestrial mammals, such as upright, columnar limbs and barrel-shaped trunks, sauropods evolved some unique features, such as the extremely long necks and diminutive heads they are famous for.


Though the largest Sperm whales weigh up to 50 tons and and the smallest bat barely reaches a gram, they share something in common.

They both use echolocation, biological sonar, for hunting.

Echolocation systems are one of nature's most successful specializations. About 1,100 species of bats and roughly 80 species of toothed whales use the technique – that's 25% of all mammals. But why did such different animals as whales and bats evolve the same technique? It isn't biological kinship, bats and whales are no closer related to each other than all the other mammals that descended from the land vertebrates around 200 million years ago.


Pigs, jellyfish and zebrafish don't seem to have much in common with each other, much less humans, but the different species are all pieces of a puzzle which is helping to solve the riddles of diseases in humans - like hereditary forms of diseases affecting the nervous system, such as Parkinson's disease, Alzheimer's disease, autism, epilepsy and the motor neurone disease ALS. 

In a new project, Aarhus University scientists focused on a specific gene in pigs. The gene, SYN1, encodes the protein synapsin, which is involved in communication between nerve cells. Synapsin almost exclusively occurs in nerve cells in the brain. Parts of the gene can thus be used to control an expression of genes connected to hereditary versions of the aforementioned disorders.


A new study has revealed that the ancestors of chelicerates (spiders, scorpions, etc.) branched off from the family tree of other arthropods, such as including insects, crustaceans and millipedes, more than half a billion years ago.


Bees are more genetically related to ants than they are to social wasps such as yellow jackets and paper wasps, according to a new paper.

 Ants, bees and stinging wasps all belong to the aculeate (stinging) Hymenoptera clade, the insect group in which social behavior is most extensively developed, said senior author and ant specialist Phil Ward, professor of entomology at UC Davis. 

The use of genome sequencing and bioinformatics answers a piece of a long-standing, unanswered evolutionary puzzle. Previously it was thought that ants and bees were distantly related, with ants being closer to certain parasitoid wasps.


The great angiosperm radiation of the mid-Cretaceous, the dramatic explosion of flowering plant species that occurred about 100 million years ago, is thought to have been good news for evolving mammals, providing them with new options for food and habitat. 

Previous literature suggested the spread of angiosperms, along with the evolution of pollinating insects, may have spurred an increase in the diversity of mammals. The idea made sense: The radiation would likely have resulted in more food sources from seeds, fruits, leaves and insects.

Not always. 


Before there was life on Earth, there was a primordial soup of molecules, and at some point a specialized molecules began replicating. This self-replication kick-started a biochemical process that would lead to the first organisms.

How those molecules began replicating has been one of science's enduring mysteries.

In the early 1980s, researchers found that ribozymes — RNA enzymes — act as catalysts. It was evidence that RNA can be both the blueprints and the chemical catalysts that put those blueprints into action. This finding led to the "RNA World" hypothesis, which posits that RNA alone triggered the rise of life from a sea of molecules.