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Biologists estimate that there are about 5 to 100 million species of organisms living on Earth today. Evidence from morphological, biochemical, and gene sequence data suggests that all organisms on Earth are genetically related, and the genealogical relationships of living things can be represented by a vast evolutionary tree, the Tree of Life. The Tree of Life then represents the phylogeny of organisms, i. e., the history of organismal lineages as they change through time. It implies that different species arise from previous forms via descent, and that all organisms, from the smallest microbe to the largest plants and vertebrates, are connected by the passage of genes along the branches of the phylogenetic tree that links all of Life (Figure 1).

Watch this video (6:30), play with the interactive version of the 'Tree of Life' and sign up to Tree of Life updates at http://www.wellcometreeoflife.org. This six-minute Tree of Life video appeared on the BBC One programme 'Charles Darwin and the Tree of Life' narrated by David Attenborough.

Séguin, a research scientist in forest genomics with the Canadian Forest Service, inserted bacterial DNA into spruces that effectively made them immune to spruce budworm, a pest that can chew needles off tens of millions of hectares of trees in a single outbreak. While there is controversy over genetic engineering, some scientists say it could also help fight climate change by creating trees that grow bigger, faster, resist disease and can even turn carbon into a stable white powder that falls to the ground - in other words, trees that would be better at pulling carbon from the atmosphere.

A phylogenetic tree, also known as a phylogeny, is a diagram that depicts the lines of evolutionary descent of different species, organisms, or genes from a common ancestor. Phylogenies are useful for organizing knowledge of biological diversity, for structuring classifications, and for providing insight into events that occurred during evolution. Furthermore, because these trees show descent from a common ancestor, and because much of the strongest evidence for evolution comes in the form of common ancestry, one must understand phylogenies in order to fully appreciate the overwhelming evidence supporting the theory of evolution.

But now, a century and a half later, scientists from 11 different institutions have joined forces to amass all of that information, plus new data, to create the most comprehensive version of the tree so far. As detailed in a recent article in Proceedings of the National Academy of Sciences, the new Tree of Life shows how 2.3 million different types of animals, plants, fungi and microbes are interconnected, and how those relationships have diverged since life began on Earth more than 3.5 billion years ago.

Redwood trees, those ancient living monuments to California's past, are as mysterious to science as they are magnificent, so a team of researchers led by a San Francisco conservation group is attempting to unlock the genetic secrets of the towering conifers. Scientists affiliated with the nonprofit Save the Redwoods League are attempting for the first time to sequence the genomes of coast redwood trees and their higher-elevation cousins, the giant sequoias, a complex and expensive undertaking that experts hope will help preserve the trees' ancient groves as the climate changes over the next century.

The data comes from the open Tree of Life Project, a collaboration among biologists and other scientists around the world. It contains decades' worth of work in phylogeny, evolutionary history of and relationships among groups of organisms. The project is about a year away from a complete tree of all life, Rosindell said. He wanted a system in place that could visualize it as soon as it's ready. Right now, OneZoom only contains mammals, but that's still more than 5,000 species, all correlated with each other and color-coded according to their threat levels. Rosindell has big plans for the rest, and he even wants to build a searchable app for smartphones, showcasing the history and relationships between all life on Earth.

The Tree of Life Web Project (ToL) is a collaborative effort of biologists and nature enthusiasts from around the world. On more than 10,000 World Wide Web pages, the project provides information about biodiversity, the characteristics of different groups of organisms, and their evolutionary history (phylogeny).

Paul Strode describes the HHMI BioInteractive Click and Learn activity on DNA sequencing and phylogenetic trees. He describes how it teaches students DNA sequence alignment, and how those sequence differences allow researchers to determine relationships between species. Visit www.biointeractive.org/phylo-tree to use the interactive resource, and to find related materials. Subscribe to the BioInteractive YouTube channel to get the latest educator tips!

A team of scientists unveiled a new tree of life on Monday, a diagram outlining the evolution of all living things. The researchers found that bacteria make up most of life's branches. And they found that much of that diversity has been waiting in plain sight to be discovered, dwelling in river mud and meadow soils.

Customize visualization of tree of life.

This Click and Learn explains how DNA sequences can be used to generate such trees, and how to interpret them.

The hollow Cola tree growing in a remote area of southeastern Guinea was once home to thousands of bats routinely hunted and killed by the neighborhood children. It was also a popular spot to play. A year ago, one child in particular lived within fifty meters of the tree: a two-year-old boy who died in December 2013 and later was identified as the first person in west Africa known to have developed Ebola.

Part 2 of 2. David Attenborough explains how early sea life developed and adapted to dry land, becoming Reptiles and Amphibians. After the era of the Dinosaurs came to a sudden end, Mammal species began to proliferate. From BBC 1 documentary 'Charles Darwin and the Tree of Life'.

When it comes to charting the tree of life, the most important difference between humans and sharks isn't limbs versus fins or even lungs versus gills. It all comes down to our skeletons. Sharks' skeletons are made of cartilage, placing them along with rays and skates in a group of jawed vertebrates called cartilaginous fish. Humans-along with most other living vertebrates-belong to the same group as bony fish, whose skeletons are made of bone. Scientists knew that these groups diverged more than 420 million years ago, but what the last common ancestor looked like remained a mystery. Now, new discoveries inside the head of a small fossil fish from Siberia may provide some clues.

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.

The seashell phylogeny and evolution activity is an interactive online activity that can be done in class or assigned as homework. The Teacher's Guide describes supporting resources that can be used to teach students about seashells and a pre-activity exercise that uses the downloadable picture cards to familiarize students with the concept of sorting organisms.

The article "The difference makers" (10.9 readability score) gives an overview of transposons, or "jumping genes," and how these bits of genetic material have affected genetic variety and evolution in humans and other organisms. Students can focus on details reported in the article, follow connections to earlier articles about transposons and human evolution, explore crosscurricular connections to other major science topics, and construct a phylogenetic tree of primate evolution based on the locations of retroviral sequence insertions in chromosome 21

2 minute animation, (includes full body animation rendition of Australopithicus) A recent study of fossil shoulder bones from a human ancestor reveals that this ancient relative was still well adapted to living in trees, even after the evolution of bipedalism. Studying features like these helps scientists to better understand when modern humans moved away from a partly arboreal lifestyle and transitioned to living exclusively on the ground.

Massive vines that blanket the southern United States, climbing high as they uproot trees and swallow buildings. A ravenous snake that is capable of devouring an alligator. Rabbit populations that eat themselves into starvation. These aren't horror movie concepts - they're real stories. But how could such situations exist in nature? Jennifer Klos gives the facts on invasive species.