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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

Inthis lesson students will enter the world of the genome, learning about humanhistory and evolution by examining information about human, Neanderthal, andchimpanzee DNA. Using web interactives and videosfrom The Human Spark, studentswill be introduced to the ambitious Human Genome Project, learn about thegenetic similarities and differences between human beings and our hominidancestors, explore how specific genes manifest themselves in differentorganisms, and discover how genetic information can help us trace a path ofhuman migration all the way back to our earliest ancestors.

A keenly observant young man named Tony Allison, working in East Africa in the 1950s, first noticed the connection and assembled the pieces of the puzzle. His story stands as the first and one of the best understood examples of natural selection, where the selective agent, adaptive mutation, and molecule involved are known-and this is in humans to boot. The protection against malaria by the sickle-cell mutation shows how evolution does not necessarily result in the best solution imaginable but proceeds by whatever means are available.

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.

Have you ever wondered why people look the way they do? Why our hands and feet have five digits instead of six? Why we stand on two legs instead of four? It took 350 million years of evolution to produce the amazing machine we call the human body and in Your Inner Fish, a three-part series based on the best-selling book of the same name, author and evolutionary biologist Dr. Neil Shubin looks into the past to answer these and other questions.

One of my favorite "proofs" of evolution is the recurrent laryngeal nerve (RLN)-the nerve that innervates the larynx from the brain, helping us speak and swallow. It takes a very circuitous course, looping from the brainstem down around the aorta and then back up to the larynx. Here's its course in humans:

DNA to Darwin allows 16-19 year-old school students to explore the molecular evidence for evolution through practical bioinformatics activities that use data analysis tools and molecular data. Each of the activities on this web site centres around an engaging story from recent research in molecular genetics encompassing microbiology, plant and animal biology and human evolution.

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.

All adult mammals but humans are lactose intolerant. Follow human geneticist Spencer Wells, director of the Genographic Project of the National Geographic Society, as he tracks down the genetic and societal changes associated with the ability to digest lactose as adults-or lactose tolerance.

A Cornell study offers further proof that the divergence of humans from chimpanzees some 4 million to 6 million years ago was profoundly influenced by mutations to DNA sequences that play roles in turning genes on and off.

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

Human evolution - mutation producing common traits

This hands-on activity, used in conjunction with the film The Making of the Fittest: Natural Selection in Humans, teaches students about population genetics, the Hardy-Weinberg principle, and how natural selection alters the frequency distribution of heritable traits. It uses simple simulations to illustrate these complex concepts and includes exercises such as calculating allele and genotype frequencies, graphing and interpretation of data, and designing experiments to reinforce key concepts in population genetics.

All living humans originated from populations of ancestors who migrated out of Africa less than 100,000 years ago. Learn how scientists have used genetic markers to trace the migration routes and origins of modern human populations.

This interrupted case study for the flipped classroom introduces the human microbiome from the perspective of one of its occupants, Heidi Helicobacter (Helicobacter pylori).  Heidi lives in the gut of Kristen, a college student, and discusses her fellow microbial inhabitants, functions of these various microbes, and alludes to factors that can disrupt the healthy human microbiome. Students prepare for class by viewing several brief videos and then discuss in class whether Kristen should undergo a fecal microbiota transplant to treat her Clostridium difficile infection.  A lab component has students model, using colored beads, how antibiotics can act as a selective agent for drug-resistant microbes such as C. difficile. The case concludes with Kristen about to give birth to a new baby several years later.  Students listen in as Kristen's microbes discuss the formation of the new baby's microbiome. The case has been used successfully in a general biology class and could easily be adapted for a microbiology, human physiology, ecology, or evolution course.

This interrupted case study for the flipped classroom applies evolutionary genetics research to human health. Students learn about a naturally occurring, but rare, allele of the CCR5 gene, CCR5-Δ32, which provides resistance to HIV. They use data from primary literature sources to predict and interpret worldwide patterns of CCR5-Δ32 frequency distribution. They then discuss how these allele frequency patterns may have been driven by selection imposed by various diseases or by other evolutionary mechanisms. Next, they test published data using Hardy-Weinberg equilibrium to examine if CCR5-Δ32 also provides genetic resistance to West Nile virus. Finally, they complete a jigsaw discussion of Nature News articles that report on how CCR5 research is being used to develop therapies to treat HIV. Originally written for the evolution portion of a yearlong biology series for undergraduate majors, the case is also appropriate for some non-majors biology courses or, with added complexity, upper-level evolution, genetics, or cell biology courses.

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."

DNA from a man who lived in Ethiopia about 4,500 years ago is prompting scientists to rethink the history of human migration in Africa. Until now, the conventional wisdom had been that the first groups of modern humans left Africa roughly 70,000 years ago, stopping in the Middle East en route to Europe, Asia and beyond. Then about 3,000 years ago, a group of farmers from the Middle East and present-day Turkey came back to the Horn of Africa (probably bringing crops like wheat, barley and lentils with them).

n Wednesday, it happened again. Yohannes Haile-Selassie of the Cleveland Museum of Natural History and his colleagues reported finding a jaw in Ethiopia that belonged to an ancient human relative that lived some time between 3.3 and 3.5 million years. They argue that the jaw belongs to an entirely new species, which they dubbed Australopithecus deyiremeda.