Summaries | Headlines

A Gene Divided Reveals The Details Of Natural Selection (October 12, 2007) -- Scientists show how, over many generations, a single yeast gene divides in two and parses its responsibilities to be a more efficient denizen of its environment. The work illustrates, at the most ... > full story

New Insights Into The Evolution Of The Human Genome (October 9, 2007) -- Researchers have created the first evolutionary history of the duplications in the human genome that are partly responsible for both disease and recent genetic innovations. This work marks a ... > full story

Driving Force Of Evolution? Evolution Of Proteins Linked To Species' Metabolic Rate (October 8, 2007) -- "Survival of the fittest" has popularly described evolution for more than a century, but a new study provides further evidence that random genetic mutations over millions of years may also play a ... > full story

Census Of Protein Architectures Offers New View Of History Of Life (October 5, 2007) -- Protein architectures -- the three-dimensional structures of specific regions within proteins -- provide an extraordinary window on the history of life. Scientists compiled a global census of protein ... > full story

Beyond A 'Speed Limit' On Mutations, Species Risk Extinction (October 4, 2007) -- Scientists have identified a virtual "speed limit" on the rate of molecular evolution in organisms, and the magic number appears to be six mutations per genome per generation -- a level beyond which ... > full story

Could Adenine From Interstellar Dust Have Triggered Life On Earth? Elsewhere? (October 3, 2007) -- Some of the elements necessary to support life on Earth are widely known - oxygen, carbon and water, to name a few. Just as important in the existence of life as any other component is the presence ... > full story

Oxygen Probably Present 50 To 100 Million Years Earlier Than First Believed (September 27, 2007) -- Two multinational teams of scientists, including researchers from Arizona State University, are reporting that traces of oxygen appeared in Earth's atmosphere 50 to 100 million years before the ... > full story

DNA Extracted From Woolly Mammoth Hair (September 27, 2007) -- Scientists discovered that hair shafts provide an ideal source of ancient DNA -- a better source than bones and muscle for studying the genome sequences of extinct animals. They sequenced the entire ... > full story

New Method Can Reveal Ancestry Of All Genes Across Many Different Genomes (September 17, 2007) -- The wheels of evolution turn on genetic innovation -- new genes with new functions appear, allowing organisms to grow and adapt in new ways. But deciphering the history of how and when various genes ... > full story

Prehistoric Reptiles From Russia Possessed The First Modern Ears (September 12, 2007) -- Paleobiologists report that these fossil animals, found in deposits of Permian age near the Mezen River in central Russia, possessed all the anatomical features typical of a vertebrate with a ... > full story

Mice Thrive Missing Ancient DNA Sequences (September 6, 2007) -- Ultraconserved elements are DNA sequences, hundreds of base pairs long, that are 100-percent identical in mice, rats and humans. Their perfect conservation for over 80 million years was thought due ... > full story

Volcanoes Key To Earth's Oxygen Atmosphere (September 3, 2007) -- A switch from predominantly undersea volcanoes to a mix of undersea and terrestrial ones shifted the Earth's atmosphere from devoid of oxygen to one with free oxygen, according to geologists. Before ... > full story

< more recent summaries | earlier summaries >

Prokaryote -- Prokaryotes are organisms without a cell nucleus, or indeed any other membrane-bound organelles, in most cases unicellular (in rare cases, multicellular). This set of characteristics is distinct from ... > full article

Crust (geology) -- In geology, a crust is the outermost layer of a planet. The crust of the Earth is composed of a great variety of igneous, metamorphic, and sedimentary rocks. The crust is underlain by the mantle. ... > full article

Introduction to genetics -- Genetics is the study of how living things receive common traits from previous generations. These traits are described by the genetic information carried by a molecule called DNA. The instructions ... > full article

Genetic drift -- Genetic drift is the term used in population genetics to refer to the statistical drift over time of gene frequencies in a population due to random sampling effects in the formation of successive ... > full article

RNA -- Ribonucleic acid or RNA is a nucleic acid polymer consisting of nucleotide monomers that plays several important roles in the processes that translate genetic information from deoxyribonucleic acid ... > full article

Neandertal interaction with Cro-Magnons -- Neanderthals apparently co-existed with anatomically modern humans beginning some 100,000 years ago. However, about 45,000 years ago, at about the time that stoneworking techniques similar to those ... > full article

Gene -- A gene is a locatable region of genomic sequence, corresponding to a unit of inheritance, which is associated with regulatory regions, transcribed regions and/or other functional sequence regions. ... > full article

Multiregional hypothesis -- The multiregional origin hypothesis of human species holds that some, or all, of the genetic variation between the contemporary human races is attributable to genetic inheritance from either Homo ... > full article

Natural selection -- Natural selection is the phrase Charles Darwin used in 1859 for the process he proposed to explain the origin of species and their apparent adaptation to their environment. Along with the rules of ... > full article

Timeline of human evolution -- The timeline of human evolution outlines the major events in the development of humans species and the evolution of human's ancestors. It begins with the time of the origin of life and presents a ... > full article

Fossil -- Fossils are the mineralized or otherwise preserved remains or traces (such as footprints) of animals, plants, and other organisms. The totality of fossils and their placement in fossiliferous ... > full article

Timeline of evolution -- This timeline of the evolution of life outlines the major events in the development of life on the planet Earth. Dates given are estimates based on scientific evidence. In biology, evolution is the ... > full article

Recent single-origin hypothesis -- The single-origin hypothesis (or Out-of-Africa model) is one of two accounts of the origin of anatomically modern humans, Homo sapiens. Because of the scarcity of fossils and the discovery of ... > full article

Microorganism -- A microorganism or microbe is an organism that is so small that it is microscopic (invisible to the naked eye). Microorganisms are often illustrated using single-celled, or unicellular organisms; ... > full article

Precambrian -- The Precambrian is an informal name for the eons of the geologic timescale that came before the current Phanerozoic eon. It spans from the formation of Earth around 4500 Ma (million years ago) to the ... > full article

Archaeopteryx -- Archaeopteryx lithographica is the earliest and most primitive known bird. In the 1990s, the discovery of a number of well-preserved feathered dinosaurs solidified the link between dinosaurs and ... > full article

Parallel evolution -- Parallel evolution is the independent evolution of similar traits, starting from a similar ancestral condition. Frequently this is the situation in more closely related lineages, where several ... > full article

Geologic temperature record -- This article is devoted to temperature changes in Earth's environment as determined from geologic evidence on multi-million to billion (109) year time scales. The last 3 million years have been ... > full article

Evolution of the eye -- The evolution of the eye has been a subject of significant study, as a distinctive example of a homologous organ present in a wide variety of species. The development of the eye is considered by most ... > full article

Feathered dinosaurs -- The realization that dinosaurs are closely related to birds raised the obvious possibility that some dinosaurs had feathers. Fossils of Archaeopteryx include well-preserved feathers, but it was not ... > full article