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How did feathers evolve? - Carl Zimmer

How did feathers evolve? - Carl Zimmer

Researchers find a completely new DNA binding protein The basic premises underlying gene expression—when and where genes are turned on and off—were worked out in bacteria by François Jacob and Jacques Monod in the middle of the twentieth century. The expression of a gene typically relies on one or more proteins binding to a specific DNA sequence near the gene of interest. These proteins are called transcription factors since they regulate the transcription of genes into RNA, the first step in turning them into proteins. At this point, many different families of related transcription factors have been defined. And, as more and more genomes have been sequenced, it was easy to get the impression that we had a complete catalog. C. albicans is a fungus. These yeast can be “white” or “opaque." There are five transcriptional factors known to regulate white-opaque switching. They found only one gene that fit both criteria; they named it WOR3 (white-opaque regulator-3).

Curiosity, discovery and gecko feet - Robert Full UC Berkeley biologist Robert Full is fascinated with cockroach legs that allow them to scuttle at full speed across loose mesh and gecko feet that have billions of nano-bristles to run straight up walls. He's using his research to design the perfect robotic "distributed foot," adding spines, hairs and other parts to metal legs and creating versatile scampering machines. He's helped create robots, such as Spinybot, which can walk up sheer glass like a gecko -- and he even helped Pixar create more realistic insect animations in the film A Bug's Life. Robert Full on animal movement Robert Full: Engineering and evolution Robert Full: Learning from the gecko's tail

Birds and the feather did not evolve together “Which came first, the chicken or the egg?” Evolutionarily speaking, it’s a yawn of a conundrum. We know it was the egg, which evolved (with shell to enable a terrestrial lifestyle) some 300 million years ago, long before a chicken first clucked across a patch of open ground. In between the origin of the egg and the domestication of the chicken, however, there are plenty of other interesting features to consider. Take the feather. These discoveries have made the question of evolutionary origins even more interesting. A perspective in Science written by University of Texas at Austin paleontologist Julia Clarke lays out the basics of what we know so far—and where we might look for pieces of the puzzle that are still missing. The earliest “proto-feathers” were not flap-like scales; they were thin fibers that would have provided little aerodynamic advantage even if they were attached to, say, a tree-hopping glider. Feathers on modern birds perform a number of duties beyond enabling flight.

Are we ready for neo-evolution? - Harvey Fineberg Theodosius Grygorovych Dobzhansky was a prominent geneticist and evolutionary biologist, and a central figure in the field of evolutionary biology for his work in shaping the unifying modern evolutionary synthesis. Antonio Damasio's research in neuroscience has shown that emotions play a central role in social cognition and decision-making. His work has had a major influence on current understanding of the neural systems, which underlie memory, language, consciousness. Listen to his TED talk about the quest to understand consciousness. The Big Bang theory is an effort to explain what happened at the very beginning of our universe. Evolution is the change in the inherited characteristics of biological populations over successive generations. The Human Genome Project (HGP) was one of the great feats of exploration in history — an international research effort to sequence and map all of the genes - together known as the genome - of members of our species, Homo sapiens.

Fungus Is The Internet Of The Plant World Fungus. Even the word itself feels like fungus. Slimy. Dirty. Sticky. But it does appear we’ve all underestimated fungus and our beloved plants at the same time. Scientists discovered this by setting up a test with bean plants. Remarkably, plants which were not under attack themselves, but which were connected to the victim by the underground fungal network, also began to produce the defensive chemical response. He’s not exaggerating: Such symbiotic fungi colonize the roots of most plant systems, meaning this research could have impacts for the entire plant world (including those we eat, of course). Read more here and here. [Hat tip: @ejacqui] [IMAGE: via Shutterstock]

Earth's mass extinction - Peter Ward This Island Earth is a 1955 American science fiction film directed by Joseph M. Newman. It is based on the novel of the same name byRaymond F. Jones. The Rare Earth hypothesis argues that complex extraterrestrial life requires an Earth-like planet with similar circumstance and that few if any such planets exist. The Life and Death of Planet Earth is a book by Peter Ward about how the new science of astrobiology charts the ultimate fate of our world. A runaway greenhouse effect is a process in which a net positive feedback between surface temperature and atmospheric opacity increases the strength of the greenhouse effect on a planet until its oceans boil away. The Permian Extinction is the Earth's most severe known extinction event, with up to 96% of all marine species and 70% of terrestrial vertebrate species becoming extinct. The three ages of dinosaurs were marked out by geologists to distinguish among various types of geologic strata laid down tens of millions of years ago.

Fungus network 'plays role in plant communication' 10 May 2013Last updated at 03:10 ET Mycorrhizae are mutualistic - they both need and are needed by the plants whose roots they inhabit Plants can communicate the onset of an attack from aphids by making use of an underground network of fungi, researchers have found. Instances of plant communication through the air have been documented, in which chemicals emitted by a damaged plant can be picked up by a neighbour. But below ground, most land plants are connected by fungi called mycorrhizae. The new study, published in Ecology Letters, demonstrates clearly that these fungi also aid in communication. It joins an established body of literature, recently reviewed in the Journal of Chemical Ecology and in Trends in Plant Science, which has suggested that the mycorrhizae can act as a kind of information network among plants. The team concerned themselves with aphids, tiny insects that feed on and damage plants. To prevent any through-the-air chemical communication, the plants were covered with bags.

Five fingers of evolution - Paul Andersen In his talk, Paul Andersen explains the five causes of microevolution. Research one example for each cause in the human population. Use the following population simulator to simulate microevolution: Run the simulation using the default settings. Note the change in gene frequencies due to chance.

NERC - Plants use underground networks to warn of enemy attack 10 May 2013 Plants use underground fungal networks to warn their neighbours of aphid attack, UK scientists have discovered. The study, published this week in Ecology Letters , is the first to reveal plants' ability to communicate underground in this way. The research, funded by a NERC studentship with Rothamsted Research, changes our understanding of the ways in which living things interact with one another. Scientists from the University of Aberdeen, the James Hutton Institute and Rothamsted Research grew the bean plant ( Vicia faba ) in groups of five. They then infested one of the plants in each group with aphids, triggering the release of a suite of chemicals designed to repel aphids but attract wasps, one of the aphid's predators. Remarkably, plants which were not under attack themselves, but which were connected to the victim by the underground fungal network, also began to produce the defensive chemical response. Dr David Johnson, of the University of Aberdeen, led the study. Notes

How life came to land - Tierney Thys The Shape of Life series educator resources www.Shapeoflife.org Additional Shape of Life series resources (In particular, check out Bill Shear’s work TEDxSMU talk by Tierney Thys highlighting the 8 major body plans of animal evolution Beautiful imagery and rich information featuring planktonic animal life www.PlanktonChronicles.org The Tree of Life web project explores the connections and evolution of life. The World Register of Marine Species keeps a tally of all species described in the ocean. How many species inhabit Earth and how might we answer that question? Where did squid, jellyfish, and other sea creatures begin life? New videography techniques have opened up the oceans' microscopic ecosystem, revealing it to be both mesmerizingly beautiful and astoundingly complex.

Carnivorous plant has deleted most of its junk DNA Over the weekend, Nature released a paper that describes the genome of a fascinating creature with a rather unglamorous name: the bladderwort. These plants live in swampy or liquid environments and find it hard to get sufficient nutrients there, so the plants have turned carnivorous in order to survive. The bladders that give the group of related species its name are actually feeding organs. When an organism brushes up against their triggers, the bladders swell by sucking in the surrounding water, along with any organisms it carries. They then seal off, allowing the plant to digest its prey. The oddities continue at the molecular level. First, the details, then some perspective. A minimalist genome The bladderwort's 82 million base pair genome contains 28,500 genes, a number only slightly higher than those of its closest relatives. That's bizarre, because the plant has relatively little regulatory DNA. Why would deleting DNA be so favorable for these plants but not for most others?

9. Hare and Lynx Populations Once students understand the concept of populations, it is important to introduce the idea of population change. There are many reasons for population change – limited resources, predator-prey cycles, human ... Summary Once students understand the concept of populations, it is important to introduce the idea of population change. There are many reasons for population change – limited resources, predator-prey cycles, human impact, habitat change – to name but a few. In this activity, students learn to graph population data and then use their graphs to evaluate one of the most famous examples of population change, the predator-prey population cycle of the snowshoe hare and the Canada lynx. Teacher Background After learning about habitats, food webs and food chains, students can begin to discover the relationships between organisms and between organisms and their environment. Populations are always changing. Another theory is that the lynx population determines the hare population.

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