Abiogenesis Scientific hypotheses about the origins of life can be divided into a number of categories. Many approaches investigate how self-replicating molecules or their components came into existence. On the assumption that life originated spontaneously on Earth, the Miller–Urey experiment and similar experiments demonstrated that most amino acids, often called "the building blocks of life", can be racemically synthesized in conditions which were intended to be similar to those of the early Earth. Several mechanisms have been investigated, including lightning and radiation. Other approaches ("metabolism first" hypotheses) focus on understanding how catalysis in chemical systems in the early Earth might have provided the precursor molecules necessary for self-replication. Early conditions The Hadean Earth is thought to have had a secondary atmosphere, formed through degassing of the rocks that accumulated from planetesimal impactors. The earliest life on Earth Current models
List of time periods The categorization of time into discrete named blocks is called periodization. This is a list of such named time periods as defined in various fields of study. Major categorization systems include cosmological (concerning the various time periods in the origin and evolution of the Universe), geological (concerning time periods in the origin and evolution of earth) and historical (concerning time periods in the origin and human evolution). Human time periods These can be divided broadly into prehistorical (before history began to be recorded) and historical periods (when written records began to be kept). In archaeology and anthropology, human prehistory is subdivided around the three-age system. The dates for each age can vary by region. Historical periods The Americas Southeast Asia China Central Asia Africa Europe India Japan Middle East Contemporary historical periods throughout the world
DNA shows Irish people have more complex origins than previously thought -- Secret History The red-hair gene is most common in Irish blood. The blood in Irish veins is Celtic, right? Well, not exactly. Although the history many Irish people were taught at school is the history of the Irish as a Celtic race, the truth is much more complicated, and much more interesting than that ... Research done into the DNA of Irish males has shown that the old Anthropological attempts to define 'Irish' have been misguided. Research into Irish DNA and ancestry has revealed close links with Scotland stretching back to before the Ulster Planation of the early 1600s. Medieval map of Ireland, showing Irish tribes. Irish Blood: origins of DNA The earliest settlers came to Ireland around 10,000 years ago, in Stone Age times. But where did the early Irish come from? The latest research into Irish DNA has confirmed that the early inhabitants of Ireland were not directly descended from the Keltoi of central Europe. The Kingdom of Dalriada c 500 AD is marked in green. Irish Characteristics and DNA
Timeline of evolutionary history of life Visual representation of the history of life on Earth as a spiral The dates given in this article are estimates based on scientific evidence. Basic timeline In its 4.6 billion years circling the sun, the Earth has harbored an increasing diversity of life forms: Periodic extinctions have temporarily reduced diversity, eliminating: Dates are approximate. Detailed timeline In this timeline, Ma (for megaannum) means "million years ago", ka (for kiloannum) means "thousand years ago", and ya means "years ago". Hadean Eon 4000 Ma and earlier. Archean Eon 4000 Ma – 2500 Ma Proterozoic Eon 2500 Ma – 542 Ma Phanerozoic Eon 542 Ma – present The Phanerozoic Eon, literally the "period of well-displayed life", marks the appearance in the fossil record of abundant, shell-forming and/or trace-making organisms. Paleozoic Era 542 Ma – 251.0 Ma Mesozoic Era Cenozoic Era 66 Ma – present Historical extinctions See also Further reading References
List of pre-modern great powers The historical term "Great Nation", distinguished aggregate of people inhabiting a particular country or territory, and "Great Empire", considerable group of states or countries under a single supreme authority, are colloquial; use is seen in ordinary historical conversations (historical jargon). History Ancient powers Ancient Near East The term ancient Near East encompasses the early civilizations during the time roughly spanning the Bronze Age from the rise of Sumer and Gerzeh in the 4th millennium BCE to the expansion of the Persian Empire in the 6th century BCE. Sumer and Akkad Sumer (or Šumer) was one of the early civilizations of the Ancient Near East, located in the southern part of Mesopotamia (modern-day Iraq) from the time of the earliest records in the mid 4th millennium BC until the rise of Babylonia in the late 3rd millennium BC. Ancient Babylon was officially conquered by the Achemidian Persian Empire in the late 6th century BCE. Elam
Consortium for the Barcode of Life The Consortium for the Barcode of Life (CBOL) is an international initiative dedicated to supporting the development of DNA barcoding as a global standard for species identification. CBOL's Secretariat Office is hosted by the National Museum of Natural History, Smithsonian Institution, in Washington, DC. Barcoding was proposed in 2003 by Prof. Paul Hebert of the University of Guelph in Ontario as a way of distinguishing and identifying species with a short standardized gene sequence. Hebert proposed the 648 bases of the Folmer region of the mitochondrial gene cytochrome-C oxidase-1 as the standard barcode region. Dr. CBOL was created in May 2004 with support of the Alfred P. One of CBOL's primary contributions to the success of barcoding has been its outreach efforts to government agencies (agriculture, environment, conservation, and others) and international organizations (CITES, Convention on Biological Diversity, Food and Agriculture Organization) that could benefit from barcoding.
Day One The meeting began with a brief introduction by John Dupré. The first speaker was Ford Doolittleof the Dept. of Biochemistry and Molecular Biology at Dalhousie University here in Halifax. His title was The Tree of Life, from three sides now. Ford introduced the topic from three perspectives: science, philosophy, and politics. The trees aren't wildly different in most cases and it's possible to make sense of them by postulating the transfer of genes from one species to a different species. The scientific evidence shows clearly that early phylogenetic relationships among bacteria cannot be accurately represented by a single tree. The philosophical questions have to do with the usefulness of metaphors in science (e.g. tree) and the implications for understanding the history of biology. Later on, Ford made the point that we need to move beyond Darwinism to postDarwinism and I agree with this point. The next talk was by Jan SappProfessor of Biology at York University in Toronto (ON, Canada).
Dot-com bubble The period was marked by the founding (and, in many cases, spectacular failure) of a group of new Internet-based companies commonly referred to as dot-coms. Companies could cause their stock prices to increase by simply adding an "e-" prefix to their name or a ".com" to the end, which one author called "prefix investing." A combination of rapidly increasing stock prices, market confidence that the companies would turn future profits, individual speculation in stocks, and widely available venture capital created an environment in which many investors were willing to overlook traditional metrics, such as P/E ratio, in favor of basing confidence on technological advancements. The collapse of the bubble took place during 1999–2001. Bubble growth Soaring stocks "But did the kids [the often young dotcom entrepreneurs] dupe the establishment by drawing them into fake companies, or did the establishment dupe the kids by introducing them to Mammon and charging a commission on it?"
Cine au fost hominizii misterioşi cu care s-au împerecheat strămoşii noştri? O analiză genetică indică faptul că oamenii moderni s-au împerecheat cu denisovanii, neanderthalienii şi cu încă o populaţie misterioasă despre care nu se cunosc informaţii. O nouă secvenţiere a genomului provenit de la două rude extincte ale omului sugerează că aceste grupuri „arhaice” s-au împerecheat atât între ele cât şi cu oamenii mult mai mult decât se credea anterior. Cele două genomuri au provenit, unul de la neanderthalieni şi altul de la un al grup uman arhaic, de la oamenii din Denisova (denisovani). Descoperirile sugerează că încrucişarea s-a produs între membrii mai multor grupuri străvechi asemănătoare cu oamenii care trăiau în Europa şi Asia acum mai bine de 30.000 de ani. „Ceea ce par să sugereze descoperirile este că ne uităm la o lume de timpul celei din «Stăpânul Inelelor» în care trăiau multe populaţii de hominizi”, a declarat geneticianul Mark Thomas, de la University College London.
Has the ‘Human Epoch’ Begun and is a Mass Extinction Near? Nature Published on December 30th, 2010 | by Michael Ricciardi As we near 2011, I know I must try to prepare myself for 2012, and the (next) wave of apocalyptic doom-saying that, according to the ‘fin-de-cyclists’, was predicted by the ancient Mayan mathematicians over 3 thousand years ago. Of course, they never predicted an End, per se, it’s just that they only extended their 260 day, cyclical calendar* to December 22, 2012 (near the winter solstice, a fitting day to be sure); they probably thought that was just plenty. It’s easy to dismiss such cataclysmic claims as being the product of mis-educated, or under-informed, mystical types, but I remind myself that science too has fanned its share of doom and gloom scenarios…Consider the Y2K hysteria of but a decade ago. So OK, both science and pseudo-science have had their end-of-life-as-we-know-it predictions (science veils its doom saying in purely “what if?” Mayan Month Glyph: black storm, Ch’en Mayan Month Glyph: new sun , Yaxk’in’
Information Age A visualization of the various routes through a portion of the Internet. The Information Age (also known as the Computer Age, Digital Age, or New Media Age) is a period in human history characterized by the shift from traditional industry that the industrial revolution brought through industrialization, to an economy based on information computerization. The onset of the Information Age is associated with the Digital Revolution, just as the Industrial Revolution marked the onset of the Industrial Age. During the information age, the phenomenon is that the digital industry creates a knowledge-based society surrounded by a high-tech global economy that spans over its influence on how the manufacturing throughput and the service sector operate in an efficient and convenient way. The Internet The Internet was conceived as a fail-proof network that could connect computers together and be resistant to any single point of failure. Progression Library expansion Computation