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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.

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."

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.

About GeneCards®: GeneCards is a searchable, integrated database of human genes that provides comprehensive, updated, and user-friendly information on all known and predicted human genes. GeneCards extracts and integrates gene-related data, including genomic, transcriptomic, proteomic, genetic, clinical, and functional information. This is automatically mined from >100 carefully selected web sources, thereby allowing one-stop access to a very broad information base. GeneCards overcomes barriers of data format and heterogeneity, and uses standard nomenclature and approved gene symbols. It presents a rich subset of data for each gene, and provides deep links to the original sources for further scrutiny. GeneCards is widely used, and assists in the understanding of gene-related aspects of biology and medicine.

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.

This interrupted case study explores the role of cytoskeletal structures on human health, specifically on respiratory function, sperm motility, and female fertility. It follows the story of a couple struggling to conceive a child and the doctors working to help them. Students are presented with clinical histories, narrative elements, documentary-style videos, and microscopic evidence in order to determine the cause of the couple's infertility. Along the way, they learn about the three types of cytoskeletal elements and the roles these play in cellular biology and human physiology. The use of videos makes it suitable for the "flipped classroom," allowing students to prepare outside the classroom for the case study, which they then complete in class. An original video by the author on the structure and function of microtubules, microfilaments, and intermediate filaments is included. The case was developed for an introductory level general biology course and could be delivered during a unit on the cell structure and function. The case could also be used in a cell biology course.

Diabetes has a history dating back to Ancient Greece. Our treatment of it, however, is more recent and was originally made possible with the help of man's best friend. Due to physiological traits shared with humans, dogs have saved countless lives through the discovery of insulin. Duncan C. Ferguson shares the story of the canine's great contribution to man -- and how we can all reap the medical benefits.

Quintana-Murci and his colleagues also took advantage of a previously published map of areas of the human genome where Neanderthal genes are present, showing that innate immune genes are generally more likely to have been borrowed from Neanderthals than genes coding other types of proteins. Specifically, they noted that 126 innate immune genes in present-day Europeans, Asians, or both groups were among the top 5 percent of genes in the genome of each population most likely to have originated in Neanderthals. The cluster of toll-like receptor genes, encoding TLR 1, TLR 6, and TLR 10, both showed signs of having been borrowed from Neanderthals and having picked up adaptive mutations at various points in history. Meanwhile, a group led by Janet Kelso of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, used both the same previously published Neanderthal introgression map that Quintana-Murci used and a second introgression map. The researchers searched for borrowed regions of the genome that were especially long and common in present-day humans, eventually zeroing in TLR6, TLR10, and TLR1. These receptors, which detect conserved microbial proteins such as flagellin, are all encoded along the same segment of DNA on chromosome four.

Paul Andersen discusses scientific evidence of the origin of life on our planet. He begins with a brief discussion of the age of the earth and ends with the future of humanity. He includes geologic, chemical and molecular data.

This site provides biochemical methods and computer tools to allow students to use their own DNA "fingerprints" as a starting point in the study of human evolution. Two experiments are currently available, which are supported by reagents and ready-to-use kits available from Carolina Biological Supply Company.

HIV jumped from apes to humans at least four times, as evidenced by genetically distinct groups of the virus that have been detected: M, N, O, and P. While N and P have had little impact, M is responsible for the pandemic affecting millions of individuals, and O has infected another 100,000.

There are a significant number of genetics curriculum resources designed by different companies, curriculum development outlets, state curriculum designers and individual teachers. What resources are good? How do you know? As part of the Geneticist-Educator Network of Alliances (GENA) Project, a Curriculum Content Review Committee was formed to review readily available classroom resources about patterns of inheritance. Click here to see original evaluation form used by the committee and here to see the summary of the committee's review.

This case study explores the topics of diffusion, osmosis, membrane transport, and the physiological significance of glucose and insulin in the human body. The story begins with a high school athlete, Timmy, who is incredibly efficient at metabolizing carbohydrates for energy; this is where the reader is introduced to normal carbohydrate digestion and metabolism for energy within skeletal muscle cells. As Timmy enters college, he withdraws from sports and physical activity but continues to consume massive amounts of highly soluble carbohydrates, resulting in insulin resistance and ultimately type II diabetes. Throughout the case students are prompted with conceptual questions and interactive figures that require the application and transfer of information they have been introduced to. Originally written for intermediate and advanced physiology courses that cover foundational and complex concepts in science, the case is also appropriate for courses in intermediate biology, nutritional sciences, animal sciences, and exercise sciences.

Scientists and healthcare professionals initially exhibited little concern over the Zika virus even after evidence of human infection was first identified in 1952; Zika appeared to be both rare and unassociated with morbidity or mortality. Around 2015 all of this changed as journalists, scientists, public health officials, and laypeople scrambled to learn about its varied modes of transmission and devastating consequences (e.g., birth defects and autoimmune disorders). Although research continues to rapidly evolve, this case study directs students to reliable scientific sources (e.g., Centers for Disease Control and World Health Organization) that will likely continue to provide the most current information in order to explore questions such as: Where did the virus come from? How does it spread? What can we do to prevent it? Students will also consider the public health challenges and possible solutions associated with emerging infectious diseases. The case was originally written for an upper-level biology or public health course in which students already have some basic background knowledge regarding viruses, vaccines, and infectious disease.

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.

To address this issue, we have developed case studies that track the evolution of traits from their origination in DNA mutation, to the production of different proteins, to the fixation of alternate macroscopic phenotypes in reproductively isolated populations.

virtual lab on deformed amphibians with reference to original research

This groundbreaking NRDC documentary explores the startling phenomenon of ocean acidification, which may soon challenge marine life on a scale not seen for tens of millions of years. The film, featuring Sigourney Weaver, originally aired on Discovery Planet Green.

This groundbreaking NRDC documentary explores the startling phenomenon of ocean acidification, which may soon challenge marine life on a scale not seen for tens of millions of years. The film, featuring Sigourney Weaver, originally aired on Discovery Planet Green.

And as the El Nino weather system has been storming across the Pacific this season, it has stirred up ocean waters enough to cool down the original Blob off of Alaska, but at the same time helped give birth to what has been nicknamed the "Son of Blob" off the coast of Southern California. The still-warmer Alaskan waters, and Son of Blob sector are expected to continue to magnify the El Nino effect for months to come, according to Weather Underground's "Blob Watch" blog.