Evolution

Evolutionary biology sounds exciting - there wouldn't be any movies on the SyFy Channel without Gatoroids and Sharknados and other feats of life science run amok - but in reality you are going to spend a lot of time paying your dues watching sponges in mid-sneeze before you get to create an epidemic or a giant monster.

Sneezing sponges? Isn't that a little far-fetched, even for the network that brought us "Arachnoquake"? No, actually the sponge thing is real, and a new paper points to Porifera sneezing as evidence for a sensory organ in one of the most basic multicellular organisms on Earth, even though it doesn't even have a nervous system to interpret sensory information.

Backboned animals, at least the ones with jaws, have four fins or limbs, one pair in front and one pair behind.

Thanks to that random prankster known as evolution, these have been modified into a marvelous variety of fins, legs, arms, flippers, and wings. But how did our earliest ancestors settle into such a consistent arrangement of two pairs of appendages?

It's because we have a belly say theoretical biologists (yes, that's a real thing) at the University of Vienna and the Konrad Lorenz Institute for Evolution and Cognition Research. 


In the late 19th century, classification of humans was in vogue and a lot of it was done based on languages and physical characteristics. Physical anthropology and ethno-linguistics created the Aryan classification among Caucasians, meaning people of Europe and western Asia whose language descended from a common root and who shared physical/biological characteristics also.


Where do new genes come from?

It's a long standing debate in evolutionary biology but a new paper in Science Express says that new genes are created from non-coding DNA, and more rapidly than expected.


"Adam", our most common male ancestor, walked the earth 209,000 years ago, 9,000 years earlier than previously believed and within the time frame of his other half "Eve", the genetic maternal ancestor of mankind, according to a new paper. 

Writing in the European Journal of Human Genetics, Dr. Eran Elhaik from the University of Sheffield and colleagues also take the opportunity to blow up some other research, such as the discovery that the Y chromosome predated humanity (the A00 lineage) and originated in a different species through interbreeding, which dates "Adam" to be much older. 


How did we get limbs from ancestral fish fins? It's a fascinating topic, a science enigma.

Our first four-legged land ancestor came out of the sea about 350 million years ago. Watching a lungfish, our closest living fish relative, crawl on its four pointed fins gives us an idea of what the first evolutionary steps on land may have looked like. However, the transitional path between fin structural elements in fish and limbs in tetrapods remains elusive. 


Species living together are not forced to evolve differently to avoid competing with each other, a notion that that has been debated since the early days of natural selection.

By focusing on ovenbirds, one of the most diverse bird families in the world, a team conducted the most in-depth analysis yet of the processes causing species differences to evolve. They found that although bird species occurring together were consistently more different than species living apart, this was simply an artifact of species being old by the time they meet. In fact, once variation in the age of species was accounted for, coexisting species were actually more similar than species evolving separately.


 A new hand bone from a human ancestor who roamed the earth in East Africa approximately 1.42 million years ago has been found at the 'Kaitio' site in West Turkana, Kenya. 

Humans have a distinctive hand anatomy that allows us to make and use tools. Apes and other non-human primates do not have these distinctive anatomical features in their hands, and the point in time at which these features first appeared in human evolution is unknown.

The researchers suspect the bone belonged to the early human species, Homo erectus, making this bone is the earliest evidence of a modern human-like hand and indicating that this anatomical feature existed more than half a million years earlier than previously known.


The home team holds the advantage over visitors, at least in the plant world, but a handful of genetic adaptations could even the playing field, according to a new paper.

Genetic tradeoffs, in part, explain the rich diversity of species on earth. If all plants could perform well in all climates, the world would have similar flora from the poles to the Equator. Trade-offs, however, such as protection from freezing temperatures in exchange for growing larger, must be made by plants, limiting the regions where they can flourish.


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.