Evolution

Some new speculation on animal (metazoan) evolution, suggesting that it was partly mediated through a biochemical oscillator (cycler), named Life's Timekeeper, present in all animal cells. The cycler controls cell maintenance and repair, thereby determining how long cells survive (longevity) and it originated in the single-celled ancestor of all animals, which had very short cell longevity.


Inside Science -- How can you tell how a creature walked when all that you have is the head?

For many years, scientists looked to the foramen magnum – the large hole at the base of the skull where the brain connects to the spine – to find out. They believed it showed if an early human was a biped that walked on two legs, or a quadruped that walked on four. But a recent study published in the Journal of Human Evolution calls this into question.

1) Motivation (insufficient justification): Throughout the world, there is a ‘new enlightenment.’ Maintaining certain illusions has become so demanding and frustrating that increasingly people simply go for the plain truth because whatever else they say would make little difference in the reception. People witness such and thus find new courage to “call a spade a spade” without apologizing, since an apology in today's mainstream irrational discourse is a mere revealing of weakness that invites further attacks by the masses of self-righteous intellectual weaklings.

The fungal pathogen Batrachochrytrium dendrobatridis (Bd), which has been known to cause the disease chytridiomycosis and decimate frog populations for close to half a century, is causing frogs to evolve around it, according to a new study which took a step toward identifying the genetic mechanisms that makes some frogs resistant to Bd infections in their study of lowland leopard frogs in Arizona. 


If you trace our evolutionary tree way back to its roots, before the shedding of gills or the development of opposable thumbs, you will likely find a common ancestor with the amazing ability to regenerate lost body parts. Descendants of this creature, including today's salamanders or zebrafish, can still perform the feat, but humans lost much of their regenerative power over millions of years of evolution. 


While wheat has been much maligned recently for it's gluten content, and new suspicions casted about as to its nutritional value, scientists have been eager to trace the evolutionary history of wheat to better understand the pasta wheat currently available.

Since the dawn of agriculture, humans have been selecting plants to maximize both the crop yield and food benefits. But which has left the larger genomic footprint, and are there evolutionary tradeoffs with domestication?


Researchers have identified unique anatomical features in a species of blind, walking cavefish in Thailand that enable the fish to walk and climb waterfalls in a manner comparable to tetrapods, or four-footed mammals and amphibians.

The discovery of this capability, not seen in any other living fishes, also has implications for understanding how the anatomy that all species need to walk on land evolved after the transition from finned to limbed appendages in the Devonian period, which began some 420 million years ago.

This research is reported in Scientific Reports ("Tetrapod-like pelvic girdle in a walking cavefish," by Brooke E. Flammang, Daphne Soares, Julie Markiewicz and Apinun Suvarnaraksha - http://www.nature.com/articles/srep23711.) 


Anyone that has eaten chicken knows what a drumstick is - it's the lower leg of a long, spine-like bone, more specifically the fibula, one of the two long bones of the lower leg (the outer one).

In dinosaurs, the ancestors of birds, this bone is tube-shaped and reaches all the way down to the ankle, but in evolution birds lost the lower end, and no longer connects to the ankle, being shorter than the other bone in the lower leg, the tibia. In the 19th century, scientists had noted that bird embryos first develop a tubular, dinosaur-like fibula. Only afterwards, it becomes shorter than the tibia and acquires its adult, splinter-like shape.  

Researchers have identified a common ancestral gene that enabled the evolution of advanced life over a billion years ago. The gene, found in all complex organisms, including plants and animals, encodes for a large group of enzymes known as protein kinases that enabled cells to be larger and to rapidly transfer information from one part to another. 

Plants, animals, mushrooms and more all exist because they are made up of eukaryotic cells that are larger and far more complex than bacteria. Inside of these eukaryotic cells are hundreds of organelles that perform diverse functions to keep them living, just as different organs do for the human body.


Chimpanzees have an ancient common ancestor - or genetic 'Adam' - that lived over one million years ago, according to a new paper paper in the journal Genome Research.  

The research team led by Professor Mark Jobling from the University of Leicester's Department of Genetics determined the DNA sequences of a large part of the Y chromosome, passed exclusively from fathers to sons, in a set of chimpanzees, bonobos, gorillas and orangutans. The study also looked at mitochondrial DNA (mtDNA), passed from mothers to offspring, in the same set of animals, which allowed the construction of genealogical trees that could be compared between species and subspecies - and helped the researchers to discover that the genetic 'Adam' for chimpanzees lived so far back.