Approximately 25 million years ago, an ancestor of both humans and apes genetically diverged from monkeys and lost its tail. No one had identified the genetic mutation responsible for this dramatic change in our physiology — until now. In a new study published Wednesday (Feb. 28) in the journal Nature, researchers identified a unique DNA … Read more
Scientists have unearthed 188 previously unknown types of CRISPR systems buried in the genomes of simple microorganisms. Best known as a powerful gene-editing tool, CRISPR actually comes from an inbuilt defense system found in bacteria and simple microbes called archaea. CRISPR systems include pairs of “molecular scissors” called Cas enzymes, which allow microbes to cut … Read more
After decades of debate, scientists believe they have identified the most recent ancestor of the sister to all animals via the novel use of an analytical technique. The finding settles a central question about the evolution of the entire tree of animal life. All animal life is descended from a single common ancestor — a … Read more
A lethal pulse of ultraviolet (UV) radiation may have played a role in Earth’s biggest mass extinction event, fossilized pollen grains reveal. Pollen that dates to the time of the Permian-Triassic mass extinction event, roughly 250 million years ago, produced “sunscreen” compounds that shielded against harmful UV-B radiation, the analysis found. At that time, approximately … Read more
Ancient microbes whose existence predates the rise of nucleus-carrying cells on Earth may hold the secrets to how such complex cells first came to be. Now, for the first time, scientists have grown a large enough quantity of these microbes in the lab to study their internal structure in detail, Science reported. Researchers grew an … Read more
Charles Darwin famously marveled at the “endless forms most beautiful and most wonderful” produced by evolution, and indeed, Earth today teems with an estimated 1 trillion species. But how long did it take those species to evolve? The answer varies widely across lifeforms, “depending on taxa [type of creature] and environmental conditions,” Thomas Smith, a … Read more
The Denisovans, together with the Neanderthals, are the closest extinct relatives of modern humans. It wasn’t until 2010 that scientists announced that the they existed, so much about them remains unknown. However, fossil and genetic evidence suggests the Denisovans lived across a wide range of areas and conditions, from the cold mountains of Siberia and … Read more
Prehistoric giants used to populate the Earth. These behemoths included mighty dinosaurs, airplane-size pterosaurs, massive crocodiles and snakes, and even armadillos the size of cars. But today, there are just a few big animals on our planet. What happened? Why aren’t there many giants left anymore? First of all, there’s plenty of fossil evidence that … Read more
A new, enormous family tree for all of humanity attempts to summarize how all humans alive today relate both to one another and to our ancient ancestors. To build this family tree, or genealogy, researchers sifted through thousands of genome sequences collected from both modern and ancient humans, as well as ancient human relatives, according to … Read more
Genetic changes that crop up in an organism’s DNA may not be completely random, new research suggests. That would upend one of the key assumptions of the theory of evolution. Researchers studying the genetic mutations in a common roadside weed, thale cress (Arabidopsis thaliana), have discovered that the plant can shield the most “essential” genes … Read more
