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Paul Andersen details the evolutionary processes of speciation and extinction. Stickleback evolution in Lake Loberg is used as example of rapid speciation. Adaptive radiation is illustrated using the Hawaiian honeycreeper. A brief discussion of extinctions and mass extinctions is also included.

A team of scientists, in a groundbreaking analysis of data from hundreds of sources, has concluded that humans are on the verge of causing unprecedented damage to the oceans and the animals living in them. "We may be sitting on a precipice of a major extinction event," said Douglas J. McCauley, an ecologist at the University of California, Santa Barbara, and an author of the new research, which was published on Thursday in the journal Science.

Hank takes us on a trip through time to revisit the 5 major mass extinction events that have impacted species over the Earth's history, and leaves us with some thoughts about what could possibly be the sixth event - the one caused by human activities.

Habitat loss and disease in the American prairie pushed the black-footed ferret ​to the edge of extinction. Now these underground-dwelling mammals are making a comeback, through a captive-breeding program run by the U.S. Fish and Wildlife Service. There, baby ferrets-called kits-are raised and released into the wild.​

Scientists have discovered a previously unrecognized genus of extinct horses that roamed North America during the last ice age. The new findings are based on an analysis of ancient DNA from fossils of the enigmatic 'New World stilt-legged horse'

This case study introduces students to the "Red Queen Hypothesis." The hypothesis states that when two species compete for a limited resource or exist in a predator-prey relationship, in order for the antagonists to remain in relative population equilibrium, there must be ongoing and reciprocal adaptation on each side. If one species fails to adapt, it may quickly face extinction. Students are introduced to the Red Queen Hypothesis through an excerpt from Lewis Carroll's novel, Through the Looking Glass, in which Alice meets the Red Queen. They then review experiments from the research literature to evaluate the validity of the hypothesis in extant populations.  Students culminate their learning by contrasting their knowledge of the Red Queen Hypothesis to Darwinian evolutionary theory based on a passage from On the Origin of Species.  Students then craft a letter to Darwin helping to explain his "wedge" theory, a notion he originally developed but removed from later iterations of his book due to a lack of experimental evidence. Originally developed for advanced high school biology students, the case also may be used in a college-level introductory course on evolutionary biology.

Explore the diversity and evolution of birds with this web interactive based on the Wall of Birds mural. Envisioned by Cornell Lab ornithologists and realized by artist Jane Kim, the large-scale mural features species from all surviving bird families alongside a select group of extinct ancestors.

It turns out that some monkeys make better hunting partners than prey. That's the case on the Ethiopian highlands, where two unusual species have developed an equally unusual co-dependency. The relationship benefits both canine and primate, although at least one or two nearby rodent species might regret it.

While the loss of these animals is concerning for species conservation, now researchers at the University of Florida have shown that overhunting can have widespread effects on the forest itself. Overhunting leads to the extinction of a dominant tree species, Miliusa horsfieldii, or the Miliusa beech, with likely cascading effects on other forest biota.

Are we witnessing a sixth mass extinction? What factors threaten ecosystems on land and in the sea? What are researchers doing to try to conserve biodiversity and ecosystems such as tigers in Asia and coral reefs around the world? What tools do we have to avoid a global catastrophe? In six half-hour lectures, three leading scientists describe the state of biodiversity on our planet and how to face the great challenges that lie ahead.

This interactive explores different anatomical features of the human body and what they reveal about the evolutionary history we share with other organisms, including earlier, long-extinct species.

Biologists have long puzzled about how evolutionary selection, known for its ruthless requirement for efficiency, allows the existence of males - when in so many species their only contribution to reproduction are spermatozoa. But research published today in Nature shows that sexual selection - when males compete and females choose over reproduction - improves population health and protects against extinction, even in the face of genetic stress from high levels of inbreeding.

His "Photo Ark" currently houses images of more than 5,000 species, rolling past the viewer. "It would take two hours to see them all," he said. "It's supposed to just overwhelm people with what life looks like on Earth." And what might soon be extinct.

This activity guides the analysis of a published scientific figure from a study that modeled the impact of an infectious fungal disease on a bat population. In 2006, a disease called white-nose syndrome (WNS) began wiping out bat populations in North America. Because many of these bats eat insect pests, the spread of WNS may devastate ecosystems and increase pest control costs. In this study, scientists mathematically modeled the effects of WNS to estimate extinction probabilities for the little brown bat (Myotis lucifugus) population in the northeastern United States. This figure shows these probabilities projected for five annual rates of population decline. Each projection is simulated up to 100 years after WNS emerged in the population. The "Educator Materials" document includes a captioned figure, background information, graph interpretation, and discussion questions. The "Student Handout" includes a captioned figure and background information.

In this activity, students analyze scientific figures to understand principles of island biogeography theory that determine the number of species in an isolated habitat. This activity uses a jigsaw approach to explore the processes that determine the equilibrium number of species in a habitat and how they are affected by both area and isolation. Two "Student Handouts" are provided as options for the activity. The "Analyzing Graphical Data" handout engages students in graph interpretation and sensemaking from data. The "Building the Equilibrium Model" handout facilitates a scaffolded investigation of the dynamic equilibrium model of island biogeography; students construct immigration and extinction curves to demonstrate the effects of area and isolation on the equilibrium number of species. 

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What effects will the rapidly growing field of synthetic biology have on the conservation of nature? The ecological and ethical challenges stemming from this question will require a new and continuing dialogue between members of the synthetic biology and biodiversity conservation communities, according to authors of a new paper.

A new study, published on Wednesday in Molecular Biology and Evolution, identifies gene variants in Inuit who live in Greenland, which may help them adapt to the cold by promoting heat-generating body fat. These variants possibly originated in the Denisovans, a group of archaic humans who, along with Neanderthals, diverged from modern humans about half a million years ago.