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The origin of viruses remains mysterious because of their diverse and patchy molecular and functional makeup. Although numerous hypotheses have attempted to explain viral origins, none is backed by substantive data. We take full advantage of the wealth of available protein structural and functional data to explore the evolution of the proteomic makeup of thousands of cells and viruses. Despite the extremely reduced nature of viral proteomes, we established an ancient origin of the "viral supergroup" and the existence of widespread episodes of horizontal transfer of genetic information. Viruses harboring different replicon types and infecting distantly related hosts shared many metabolic and informational protein structural domains of ancient origin that were also widespread in cellular proteomes. Phylogenomic analysis uncovered a universal tree of life and revealed that modern viruses reduced from multiple ancient cells that harbored segmented RNA genomes and coexisted with the ancestors of modern cells. The model for the origin and evolution of viruses and cells is backed by strong genomic and structural evidence and can be reconciled with existing models of viral evolution if one considers viruses to have originated from ancient cells and not from modern counterparts.

Origins of Life Abiogenesis article in Wikipedia. The Origin of Life - Abiogenesis, a youtube video produced by Chuck Kopec.  A Simpler Origin for Life, an article by Robert Shapiro in Scientific American. The Miller-Urey Experiment article in Wikipedia. RNA and the RNA World Exploring the New RNA World, an essay by Thomas Cech published on the Nobel Prize website. RNA Video Clips from the HHMI website that include demonstrations of catalysis and interviews with Thomas Cech. A World Apart, an HHMI article about RNA World reseearch and the role of RNAs in medicine.  RNA World article in Wikipedia. Protocells The Emergence of Cells During the Origin of Life, an essay by Irene Chen published in Science.  What Came Before DNA? an article published in Discover featuring Jack Szostak and Steven Benner.  The Szostak Lab Astrobiology The National Astrobiology Institute, established by NASA to study life in the universe.  The SETI Institute, studying the origins, nature and prevalence of life in the universe.  Astrobiology: The Search for Life, a website hosted by the Exploratorium.

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.

18 min video- Ten thousand years ago, corn didn't exist anywhere in the world, and until recently scientists argued vehemently about its origins. Today the crop is consumed voraciously by us, by our livestock, and as a major part of processed foods. So where did it come from? Popped Secret: The Mysterious Origin of Corn tells the story of the genetic changes involved in the transformation of a wild grass called teosinte into corn.  Evidence from genetics supports archeological findings pinpointing corn's origins to a very particular time and place in Mexico

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.

31min video  The epic voyages of Darwin and Wallace led each to independently discover the natural origin of species and to formulate the theory of evolution by natural selection.

The Miller-Urey experiment was the first attempt to scientifically explore ideas about the origin of life. Stanley Miller simulated conditions thought be common on the ancient Earth. The purpose was to test the idea that the complex molecules of life (in this case, amino acids) could have arisen on our young planet through simple, natural chemical reactions. The experiment was a success in that amino acids, the building blocks of life, were produced during the simulation. The finding was so significant that it kick started an entirely new field of study: Prebiotic Chemistry. Scientists now have reason to believe that the gases used in the Miller-Urey simulation were not actually the same as those of the ancient atmosphere. Because of this, many experiments have since been done, testing a wide variety of atmospheres and different environmental conditions. The results are overwhelming: the molecules of life can form under a wide variety of ancient Earth-like conditions. Many questions about the origin of life remain to be answered but these findings give strong support to the idea that the first living cells on Earth may have emerged from natural chemical reactions.

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.

Darwin's theory of biological evolution helps us understand how simple life forms can give rise to complex lifeforms, but how did the first reproducing creatures come about? The origin of life needs its own explanation.

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.

3:09 video RNA may have been the origin of life on Earth. Go on a whirlwind tour of RNA's evolving role through billions of years of evolutionary history. Play the RNA Lab: http://www.pbs.org/wgbh/nova/labs/lab...

The possibilities of pseudo-peptide-DNA mimics like PNA (peptide nucleic acid) having a role for the prebiotic origin of life prior to an RNA world is discussed on the basis of literature data showing that this type of molecules might have formed on the primitive earth (or other places in the universe), as well as data indicating the possibilities of template-directed PNA chemical replication and ligation. In particular, the merits of an achiral prebiotic genetic material is discussed.

In this case study, a college student named "Blake" winds up in the emergency room after he experiences a panic attack brought on by drinking a mixture of beverages containing caffeine and alcohol. His panic attack results in a severe episode of hyperventilation. The alcohol he has consumed has the added effect of making the situation worse by impairing Blake's perception and judgement. Through this case study, students learn about acid/base chemistry as they explore hyperventilation, the Bohr effect, the Haldane effect, and how alcohol and stimulants such as caffeine can affect the acid-base balance in the body. This case was originally designed for a flipped classroom, and the associated videos, including one developed by the author, contain foundational information to lead students through basic chemistry and help them connect daily activities to homeostasis and the Bohr effect. Originally written for a general biology course in which general chemistry concepts are discussed, the case could easily be modified for use in an anatomy and physiology course.

This is a 3.5 minute HD dramatic video choreographed to powerful music, which introduces the viewer to the Origins of LIFE on Earth. It is designed as a motivational "trailer" to be shown by Biology and Life Science teachers in middle and high school and college as a visual "Introduction" to the topic of how life began.

article summarizing key findings

Origins of life with self-replicating molecules

Origin of life - volcanic pools - ocean floor - outer space

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."

Researchers have now created the first molecules of RNA, DNA's singled-stranded relative, that are capable of copying almost any other RNAs. The discovery bolsters the widely held view among researchers who study the origin of life that RNA likely preceded DNA as the central genetic storehouse of information in the earliest cells some 4 billion years ago.

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.