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The tale is further muddled by Chinese fossils analysed over the past four decades, which cast doubt over the linear progression from African H. erectus to modern humans. They show that, between roughly 900,000 and 125,000 years ago, east Asia was teeming with hominins endowed with features that would place them somewhere between H. erectus and H. sapiens, says Wu (see'Ancient human sites'). "Those fossils are a big mystery," says Ciochon. "They clearly represent more advanced species than H. erectus, but nobody knows what they are because they don't seem to fit into any categories we know."

For years whale evolution was characterized by speculation and limited evidence. Evolution critics even focused on whales as a means to criticize evolutionary theory. Now whale evolution represents one of the best examples of "macroevolution." This "clicker case" uses this fascinating story of historical irony as a backdrop to the study of whale evolution. First, students study an array of whale fossils to learn how evolution is properly viewed as a branching, relationship-based process, not a linear, progressive, "chain-of-being." Using this view they learn how scientists seek to reconstruct past relationships and study transitional features, not search for "missing links." Students then learn that evidence for macroevolution relies on several lines of independent evidence from fossils, comparative anatomy, embryology, genetics, and paleoecology. With a focus on macroevolution, this case makes a critical contribution to evolution education. It could work well in a lower level undergraduate biology / evolution / paleontology course (non-majors or majors), or in an upper-level evolution course, perhaps early in the semester as a primer for related topics.

Anthracobunidae is an Eocene family of large mammals from south Asia that is commonly considered to be part of the radiation that gave rise to elephants (proboscideans) and sea cows (sirenians). We describe a new collection of anthracobunid fossils from Middle Eocene rocks of Indo-Pakistan that more than doubles the number of known anthracobunid fossils and challenges their putative relationships, instead implying that they are stem perissodactyls.

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.

This animated short film tells the engaging tale of the discovery of the coelacanth. In 1938, South African museum curator Marjorie Courtenay-Latimer came across a strange blue fin poking out of a pile of fish. With its fleshy, lobed fins and its tough armored scales, the coelacanth did not look like any other fish that exists today. The coelacanth belongs to a lineage that has remained virtually unchanged for hundreds of millions of years-earning it the description of a "living fossil."

But then on Dec. 22, 1938, Marjorie Courtenay-Latimer came across a strange blue fin poking out of a pile of fish that struck her as extraordinary. With its fleshy, lobed fins and its tough armored scales, the specimen looked very unlike fish we see in our oceans today. That is because the coelacanth has managed to survive in roughly its current form for hundreds of millions of years. In the course of researching this film, we learned all kinds of amazing facts about the coelacanth. For instance, unlike most fish, they give birth to live young. They produce eggs the size of grapefruits, which then hatch internally. From video footage taken by the explorer Hans Fricke - which we used as inspiration for our sets and puppets - we know coelacanths are prone to some odd behavior. They've been spotted doing headstands underwater.

The origins of the species known as 'the hobbit' - a human relative only a little over a metre tall - have been debated ever since its discovery in 2004. Now new fossils may reveal the ancestors of this strange species and help us to understand its history.

 Trilobites may be the archetypal fossils, symbols of an archaic world long swept beneath the ruthless road grader of time. But we should all look so jaunty after half a billion years.

A researcher has gathered a piece of evidence that helps shed light on the evolutionary transition from soft-bodied animals with no well-defined heads to hard-bodied animals that sported heads. The clue comes from one of the oldest fossilized brains ever found-a more than 500 million-year-old specimen of the Cambrian arthropod Odaraia alata found in western Canada.

Comparing features of a 4.4-million-year-old fossil skeleton to those of human and chimpanzee skeletons sheds light on our evolutionary history.

To look at the evolution of modern bird feathers, we must start a long time ago, with the dinosaurs from whence they came. We see early incarnations of feathers on dinosaur fossils, and remnants of dinosaurs in a bird's wish bone. Carl Zimmer explores the stages of evolution and how even the reasons for feathers have evolved over millions of years.

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.

Imagine what we could learn about diseases by studying the history of human disease, from ancient hominids to the present. But how? TED Fellow Christina Warinner is an achaeological geneticist, and she's found a spectacular new tool - the microbial DNA in fossilized dental plaque.

Scientists discovered a new retrovirus "fossil" found in the common vampire bat which is homologous to retroviruses in rodents and primates. The results suggest the recent circulation of an active infectious retrovirus and cross-species transmission. The study has been published in the scientific journal Journal of Virology.

High on Bolivia's semiarid Andean plains at more than 12,000 feet and subject to climatic whims, the shallow saline lake has dried up before only to rebound to a size twice the area of Los Angeles. But recovery may no longer be possible, scientists say. "This is a picture of the future of climate change," said Dirk Hoffman, a German glaciologist who studies how rising temperatures from the burning of fossil fuels has accelerated glacial melting in Bolivia.

In this article, we'll examine scientific ideas about the origin of life on Earth. The when of life's origins (3.53.53, point, 5 billion years ago or more) is well-supported by fossils and radiometric dating. But the how is much less understood. In comparison to the central dogma or the theory of evolution, hypotheses about life's origins are much more...hypothetical. No one is sure which hypothesis is correct - or if the correct hypothesis is still out there, waiting to be discovered.

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'

5 minute video: The evolution of whales has been a mystery. How did a large, big-brained mammal -- air-breathing, warm-blooded, giving birth to live young -- come to live entirely in water, when mammals evolved on land?