549 posts tagged with Evolution.
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"dawn of the deed"

Secrets of T-Rex sex! An interview with John Long, author of The Dawn of the Deed: The Prehistoric Origins of Sex. Long's four-part series on Evolution: This View of Life - 1) Down and Dirty in the Devonian; 2) Palaeozoic Paternity Problems; 3) From Bones to Behavior; 4) From Clasper to Penis. Also a Scientific American video ("Long discusses a fossil central to this new view of the origin of copulation and live birth: a 375-million-year-old expectant mother fish dubbed Materpiscis attenboroughi").
posted by flex on Oct 30, 2012 - 23 comments

Does success spell doom for Homo sapiens?

State of the Species: Will the unprecedented success of Homo sapiens lead to an unavoidable downfall? [Via]
posted by homunculus on Oct 28, 2012 - 46 comments

The players in a mutualistic symbiosis: insects, bacteria, viruses, and virulence genes.

One of the many problems farmers of various kinds of legumes need to deal with is the pea aphid. They reproduce incredibly fast and live by sucking the sap out of the plants, an electron micrograph of one in action. However, while they are terrifying parasites of legumes, they have their own yet more horrific parasites, a parasitoid wasp. Here is a really nice close up picture of one doing its thing, a video of the act, and here is a brain meltingly horrific video of a dissection of the mummified aftermath 8 days later. Essentially, these wasps deposit their eggs in a pea aphid and the growing larva feeds on it, developing there for about a week, and then consuming the host from the inside out like a Xenomorph. When it’s done, the wasp larva dries the aphid’s cuticle into a papery brittle shell and an adult wasp emerges from the aphid mummy. Legume farmers love them, and you can even order their mummies online these days. However, farmers noticed that the wasps didn't work as effectively on all of the aphids, and so researchers went to work figuring out why. It turns out that all aphids have a primary bacterial endosymbiont living inside their cells, in addition to and just like a mitochondria, and that many have some combination of five other secondary endosymbionts. Interestingly, two of those other five, Hamiltonella defensa and Serratia symbiotica have been shown to confer varying levels of resistance to the parasitoid wasp, allowing the aphid to survive infection. However, it turns out that there is yet one more layer to this story, [more inside]
posted by Blasdelb on Oct 22, 2012 - 50 comments

Where The Wild Things Really Are

Maurice Sendak's (probable) inspiration. Campbell's blog is the antidote for anyone bored with religion: Barbarella and Xenu, evolution from the simple to... the simple, how God evolved (possibly backwards), and more. [more inside]
posted by EnterTheStory on Oct 22, 2012 - 11 comments

Virulence-transmission trade-offs and population divergence in virulence

"Why do parasites harm their hosts? Conventional wisdom holds that because parasites depend on their hosts for survival and transmission, they should evolve to become benign, yet many parasites cause harm. Theory predicts that parasites could evolve virulence (i.e., parasite-induced reductions in host fitness) by balancing the transmission benefits of parasite replication with the costs of host death. This idea has led researchers to predict how human interventions—such as vaccines—may alter virulence evolution, yet empirical support is critically lacking." Two papers demonstrate empirical evidence for related models predicting the origin of virulence: [more inside]
posted by Blasdelb on Oct 21, 2012 - 23 comments

Baby we were born to run.

In this sprightly talk (transcript and video) Daniel Lieberman describes why our bodies are so good at running long distances, how our social intelligence developed and how modernity and capitalism require us to learn (or relearn) how to use our bodies. (May inspire tolerance for people who wear five-fingered shoes.) Prof. Lieberman studies human evolution at Harvard where he focuses on heads and feet. (via Tyler Cowen)
posted by noway on Oct 20, 2012 - 40 comments

The Puzzle of Plastid Evolution

The Puzzle of Plastid Evolution: A comprehensive understanding of the origin and spread of plastids remains an important yet elusive goal in the field of eukaryotic evolution. Combined with the discovery of new photosynthetic and non-photosynthetic protist lineages, the results of recent taxonomically broad phylogenomic studies suggest that a re-shuffling of higher-level eukaryote systematics is in order. Consequently, new models of plastid evolution involving ancient secondary and tertiary endosymbioses are needed to explain the full spectrum of photosynthetic eukaryotes. [Full Text HTML] [Full Text PDF] [more inside]
posted by Blasdelb on Oct 20, 2012 - 8 comments

Mitigating Mutational Meltdown in Mammalian Mitochondria

Mitigating Mutational Meltdown in Mammalian Mitochondria PLoS Biol 6(2): e35. [The PDF, where you can read the paper in its much prettier intended format.]
Mitochondria are remarkable microorganisms. About two billion years ago, their distant free-living ancestors hooked up with a truly foreign lineage of archaebacteria and started a genomic merger that led to the most successful coevolved mutualism on the planet: the eukaryotic cell. Along the way, evolving mitochondria lost a lot of genomic baggage, entrusted their emerging hosts with their own replication, sorted out genomic conflicts by following maternal inheritance, and have mostly abstained from sex and recombination. What mitochondria did retain was a subset of genes that encode critical components of the electron transport chain and ATP synthesis enzymes that carry out oxidative phosphorylation. Because mitochondria house the biochemical machinery that requires us to breathe oxygen, it was first assumed that mitochondrial genes would show very slow rates of molecular evolution. So it was big news almost 30 years ago when mitochondrial DNA (mtDNA) evolution was observed to be quite rapid [1]. How could the genes for a highly conserved and critical function sustain the consequences of high mutation pressure and permit rapid rates of nucleotide substitution between species? Without the benefits of recombination, where offspring can carry fewer mutations than either parent, mutations should accumulate in mitochondrial genomes through the random loss of less-mutated genomes, a process referred to as Muller's ratchet [2,3]. How have mitochondria avoided a mutational meltdown, or at least significant declines in fitness?
Here is a jaw droppingly beautiful 3D animation of what Mitochindria look like in action. [more inside]
posted by Blasdelb on Oct 19, 2012 - 37 comments

Constitutive formation of caveolae in a bacterium.

Constitutive formation of caveolae in a bacterium. [Full Text]
Caveolin plays an essential role in the formation of characteristic surface pits, caveolae, which cover the surface of many animal cells. The fundamental principles of caveola formation are only slowly emerging. Here we show that caveolin expression in a prokaryotic host lacking any intracellular membrane system drives the formation of cytoplasmic vesicles containing polymeric caveolin. Vesicle formation is induced by expression of wild-type caveolins, but not caveolin mutants defective in caveola formation in mammalian systems. In addition, cryoelectron tomography shows that the induced membrane domains are equivalent in size and caveolin density to native caveolae and reveals a possible polyhedral arrangement of caveolin oligomers. The caveolin-induced vesicles or heterologous caveolae (h-caveolae) form by budding in from the cytoplasmic membrane, generating a membrane domain with distinct lipid composition. Periplasmic solutes are encapsulated in the budding h-caveola, and purified h-caveolae can be tailored to be targeted to specific cells of interest.
Elio Schaechter writes in plain English about how fantastically amazing and unexpected the researchers actually pulling this off is, and he also talks about it in more detail in his podcast.
posted by Blasdelb on Oct 18, 2012 - 22 comments

Provirophages and transpovirons as the diverse mobilome of giant viruses

Provirophages and transpovirons as the diverse mobilome of giant viruses
Abstract: A distinct class of infectious agents, the virophages1 that infect giant viruses of the Mimiviridae family, has been recently described. Here we report the simultaneous discovery of a giant virus of Acanthamoeba polyphaga (Lentille virus) that contains an integrated genome2 of a virophage (Sputnik 2), and a member of a previously unknown class of mobile genetic elements3, the transpovirons4. The transpovirons are linear DNA elements of ∼7 kb [kilobases]5 that encompass six to eight protein-coding genes, two of which are homologous6 to virophage genes. Fluorescence7 in situ hybridization8 showed that the free form of the transpoviron replicates within the giant virus factory and accumulates in high copy numbers inside giant virus particles, Sputnik 2 particles, and amoeba cytoplasm. Analysis of deep-sequencing data showed that the virophage and the transpoviron can integrate9 in nearly any place in the chromosome of the giant virus host and that, although less frequently, the transpoviron can also be linked to the virophage chromosome. In addition, integrated fragments of transpoviron DNA were detected in several giant virus and Sputnik genomes. Analysis of 19 Mimivirus strains revealed three distinct transpovirons associated with three subgroups of Mimiviruses. The virophage, the transpoviron, and the previously identified self-splicing introns10 and inteins11 constitute the complex, interconnected mobilome12 of the giant viruses and are likely to substantially contribute to interviral gene transfer.
[Full Text PDF] and two explanations in English [more inside]
posted by Blasdelb on Oct 16, 2012 - 28 comments

The Secret Lives of Raccoons

"In an effort to outwit raccoons, are we pushing their brain development and perhaps even sending them down a new evolutionary path? Using high-definition, infrared cameras that turn pitch dark into daylight ... Raccoon Nation [alt link] achieves something that has never been done before: it intimately follows a family of urban raccoons over the course of six months as the young – under the watchful eye of their mother – grow, develop, and begin to find their way in the complex world of a big city." "Raccoon populations have grown twenty-fold in North American cities over the last seventy years. And as this documentary will show, city life is changing raccoons in remarkable ways." (45:08 min. video)
posted by Jasper Friendly Bear on Oct 13, 2012 - 42 comments

"I attempted to repeat the experiment, however once my assistant discovered that I didn’t really have any tuna, she declined to participate in any further tests."

The Pliocene Pussy Cat Theory (which originally appeared in The Annals of Improbable Research) argues that the human ancestor Australopithecus domesticated cats for hunting, defense and harvesting static electricity to make it easier to climb trees. The theory, which was proposed by Lorenzo Love, is a parody of the Aquatic Ape Hypothesis (which is critiqued here and in shorter form here). Whether you know about the Aquatic Ape Hypothesis or not, the Pliocene Pussy Cat Theory, and Love's follow-up, the Subterranean Ape Theory, will completely alter your understanding of human evolution.
posted by Kattullus on Oct 13, 2012 - 14 comments

Eating the plate instead of the food

With the possible exception of the Nobel awards, physicists seem to get all the press these days, whether they're doing quantum level work at the LHC, or cosmology via the latest satellite data. Biologists, not so much. It's too bad, because Richard Lenski is running one of the great evolutionary experiments of our time, and it's producing interesting results. [more inside]
posted by CheeseDigestsAll on Oct 8, 2012 - 34 comments

The World of Life

The Man Who Wasn't Darwin. 2009 was Darwin's Year. 2013 will be the Year of Alfred Russel Wallace. The title and last link lead to a recent, excellent website, Wallace Online. Read the biography and proceed from there.
posted by Substrata on Sep 27, 2012 - 6 comments

Pertussis Epidemic — Washington, 2012

Since mid-2011, a substantial rise in pertussis [Whooping Cough] cases has been reported in the state of Washington. In response to this increase, the Washington State Secretary of Health declared a pertussis epidemic on April 3, 2012. By June 16, the reported number of cases in Washington in 2012 had reached 2,520 (37.5 cases per 100,000 residents), a 1,300% increase compared with the same period in 2011 and the highest number of cases reported in any year since 1942 [Make sure you don't miss Figure 1]. Commentators are already drawing corellations with the fact that Washington State leads the nation in vaccine non-compliance, Washington State's recent cutbacks in public health funding, and increases in the number of uninsured (PDF). [more inside]
posted by Blasdelb on Sep 27, 2012 - 111 comments

" the difficulty of disentangling culture and biology."

IT AIN’T NECESSARILY SO: 'How much do evolutionary stories reveal about the mind?' [more inside]
posted by the man of twists and turns on Sep 20, 2012 - 118 comments

Sex crazed, but not too picky

Nature constantly engineers new and creative solutions to all sorts of problems—turning our stereotypes about sex upside-down along the way.
posted by Brandon Blatcher on Sep 17, 2012 - 16 comments

Bill Nye vs. God

Bill Nye recently described in a Youtube video why he thinks that Creationism is inappropriate for children. Representatives of the Creation Museum have a response.
posted by Betelgeuse on Sep 9, 2012 - 221 comments

use value vs. exchange value

What Is Value? What Is Money? (via via) [more inside]
posted by kliuless on Sep 1, 2012 - 15 comments

Spiders, a post about them

The fear of spiders is hardwired into most of humanity, despite the creatures often being beneficial to people. For some reason, it's the odd and scary stories about spiders that stick in our heads.
posted by Brandon Blatcher on Aug 10, 2012 - 99 comments

There is grandeur in this view of life.

The Evolution Documentary channel (autoplays video) has collected documentaries and clips about evolution available on youtube, including documentaries from BBC, Nova, and National Geographic. [more inside]
posted by ChuraChura on Aug 3, 2012 - 8 comments

The Future Forms Of Life

The Future Forms Of Life. A Film by David Lance - Story based on Theo Jansen's Kinetic Sculptures.
posted by homunculus on Jul 25, 2012 - 4 comments

Sexless Males Screw Society

Why Polygamy is Bad for Society "A new study out of the University of British Columbia documents how societies have systematically evolved away from polygamy because of the social problems it causes. The Canadian researchers are really talking about polygyny, which is the term for one man with multiple wives, and which is by far the most common expression of polygamy. Women are usually thought of as the primary victims of polygynous marriages, but as cultural anthropologist Joe Henrich documents, the institution also causes problems for the young, low-status males denied wives by older, wealthy men who have hoarded all the women. And those young men create problems for everybody."
posted by bookman117 on Jul 19, 2012 - 190 comments

Vampiric pterosaurs that bit dinosaurs

Why the world has to ignore ReptileEvolution.com
posted by themadthinker on Jul 12, 2012 - 111 comments

Nowhere is such freedom more crucial than in a science classroom

The Ohio Supreme Court has announced it will hear the appeal of John Freshwater, a Mt. Vernon eighth grade science teacher terminated after being accused of preaching Christian beliefs in class when discussing topics such as evolution and homosexuality. He was also accused of burning the image of a cross on students' arms. [more inside]
posted by roomthreeseventeen on Jul 6, 2012 - 146 comments

Nessie and Noah

Fundamentalist Christian schools in Louisiana will soon be citing the existence of the Loch Ness monster as proof that evolution is a myth. [more inside]
posted by asnider on Jun 27, 2012 - 175 comments

The False Allure of Group Selection

Steven Pinker on the "False Allure of Group Selection", with comments by Daniel Dannett, Stewart Brand, and others. Richard Dawkins's take on group selection. Jerry Coyne's take.
posted by AceRock on Jun 25, 2012 - 55 comments

the dawn of a Star Trek generation

In Praise of Leisure - "Imagine a world in which most people worked only 15 hours a week. They would be paid as much as, or even more than, they now are, because the fruits of their labor would be distributed more evenly across society. Leisure would occupy far more of their waking hours than work. It was exactly this prospect that John Maynard Keynes conjured up in a little essay published in 1930 called 'Economic Possibilities for Our Grandchildren.' Its thesis was simple. As technological progress made possible an increase in the output of goods per hour worked, people would have to work less and less to satisfy their needs, until in the end they would have to work hardly at all... He thought this condition might be reached in about 100 years — that is, by 2030." (via) [more inside]
posted by kliuless on Jun 22, 2012 - 117 comments

Bieber de novo

Evolution of music by public choice. Results are out from the DarwinTunes experiment (previously) - a Darwinian music engine working with mutating short audio loops that underwent evolutionary selection for 2,513 generations under the influence of thousands of listeners. Article in the Proc. Nat'l Acad. Sci. You can participate at the DarwinTunes web site.
posted by exogenous on Jun 19, 2012 - 41 comments

It's The A.C.C. People

WHY WE DON’T BELIEVE IN SCIENCE
posted by jjray on Jun 7, 2012 - 47 comments

Bye Bye Birdie

Soo Bin Park in Nature has reported that South Korean highschool textbook publishers will be removing examples of evolution due to demands of creationist groups [more inside]
posted by Knigel on Jun 5, 2012 - 59 comments

A visual history of evolution

Trees of Life: A Visual History of Evolution Trees of Life: A Visual History of Evolution catalogs 230 tree-like branching diagrams, culled from 450 years of mankind’s visual curiosity about the living world and our quest to understand the complex ecosystem we share with other organisms, from bacteria to birds, microbes to mammals. (More trees are visible at the Google Books site.)
posted by OmieWise on May 31, 2012 - 4 comments

0.0001 micromoles of oxygen per liter per year

If we look at how fast they metabolize, it would take them a thousand years just to reproduce themselves. They may be much older than this. There’s no way of knowing.

Microbes found deep under the North Pacific Gyre in 86-million-year-old red clay, potentially millions of years old, force us to rethink the timescales, ranges, and conditions that life can attain. (The main text of the paper is unfortunately paywalled.)
posted by jjray on May 19, 2012 - 34 comments

The successful scientist thinks like a poet but works like a bookkeeper.

Harvard sociobiologist E. O. Wilson explores The Origins of the Arts.
posted by shakespeherian on Apr 25, 2012 - 38 comments

Exquisite Beast: illustrating evolution

Exquisite Beast is a tag-team tumblr, featuring an illustrated evolution that started with this little beastie, drawn by Evan Dahm (Rice Boy comics | Making Places worldbuilding blog). The next evolution was by Yuko Ota (Johnny Wander comic | forthcoming Lucky Penny comic), the other half of this illustrious duo. But their creature does not have a simple linear evolution chart, as seen in this cladogram showing the various fan-made offshoots. Some are linked from the Exquisite Beast posts, but you can find more from the Exquisite Beast tumblr tag.
posted by filthy light thief on Mar 13, 2012 - 7 comments

The Failure of Judges and the Rise of Regulators

The Control Revolution And Its Discontents - "the long process of algorithmisation over the last 150 years has also, wherever possible, replaced implicit rules/contracts and principal-agent relationships with explicit processes and rules."
posted by kliuless on Feb 23, 2012 - 25 comments

early performances of well-known comedians

Early performances of well-known comedians, collected by mikl-em on Laughing Squid: Louis C.K. (also see The Evolution of Louis C.K., a YouTube edit of his tribute to George Carlin - previously - intercut with clips throughout his career); Jerry Seinfeld, Jay Leno, and Steven Wright; Sarah Silverman; David Letterman; Steve Martin; Robin Williams; and "What They Did Before 30 Rock". Also see posts on George Carlin, Lenny Bruce, Father Guido Sarducci, and Jerry Stiller and Anne Meara.
posted by flex on Feb 18, 2012 - 23 comments

Too Long; Do Read

The complete story of the collaboration between Asher Vollmer and Greg Wohlwend on Puzzlejuice. [more inside]
posted by howling fantods on Feb 10, 2012 - 4 comments

The First Word

The First Word. A new Electric Sheep comic by Patrick Farley on the psychedelic origins of language. [NSFW, Via]
posted by homunculus on Jan 29, 2012 - 37 comments

Extraordinarily good at copying and following

Infinite Stupidity Now, it sounds incredible. It sounds insane. It sounds mad. Because we think of ourselves as so intelligent. But when we really ask ourselves about the nature of any evolutionary process, we have to ask ourselves whether [our mechanism for generating ideas] could be any better than random, because in fact, random might be the best strategy. Mark Pagel previously, edge.org previously
posted by victors on Jan 8, 2012 - 33 comments

S'more primate fun

He was taught to use matches, a skill he picked up quickly. There’s something eerie about watching Kanzi strike a match. The way he then holds the flame — taking care not to burn himself — is remarkably human. (video)
posted by Blazecock Pileon on Dec 31, 2011 - 42 comments

SEED

SEED. "An egg and an apple build competing broadcast towers that vie for the attention of a transistor radio." [Via]
posted by homunculus on Dec 25, 2011 - 7 comments

I now have 100 skulls in my room!

My name is Jake and I am a bone collector. This is his room, where he keeps his more than 100 skulls (a contender for the years most awesome cataloguing and archiving effort [look at that organization!]). How Jake cleans up animal bones [more inside]
posted by infinite intimation on Dec 25, 2011 - 12 comments

Man the Fat Hunter

Did the disappearance of the elephant caused the rise of modern man? Humans are not good at extracting energy from plants or converting protein to energy. Without fire to allow for better conversion, fat was a vital part of early man's diet. Elephants being slower and larger than many other prey was a prime hunting target. When the number of elephants declined, man had to find other sources. Hunting smaller, faster prey resulted in a change in human evolution. Man became lighter and their brain size increased to handle the requirements for hunting enough animals to provide the necessary fat.
posted by 2manyusernames on Dec 14, 2011 - 17 comments

I didn't evolve from no flounder.

People And The Fish They Look Like
posted by empath on Dec 11, 2011 - 25 comments

Evolution and the Illusion of randomness.

Evolution and the Illusion of randomness. (By Steve Talbott at netfuture.org)
posted by seanyboy on Dec 2, 2011 - 44 comments

Brothers of chimpanzees, cousins of rats

You have certainly seen a Tree of Life at some point (not the movie; the diagram of the evolution of species). Originally conceived of by Lamarck (though there is some interesting debate on this), it was Darwin himself who popularized the concept, first in his notebook, and next as the only image in The Origin of the Species. Though they have inspired beautiful illustrations, and a large and fascinating web project to map the tree, trees of life remain problematic since taxonomy can be complicated. One truly stunning way of redrawing the tree is the Hillis Plot, which maps 3,000 species by genetic similarity. You can print out the amazing illustration here, but, even though the Plot only contains 0.18% of named species, it needs to be 1.5 meters square to be legible. The Hillis Plot has been appearing in art, notably (and meta-rifficly) this one carved into an English oak, and, of course, tattoos.
posted by blahblahblah on Nov 10, 2011 - 19 comments

Time Tree

TimeTree is a public knowledge-base for information on the evolutionary timescale of life. A search utility allows exploration of the thousands of divergence times among organisms in the published literature. A tree-based (hierarchical) system is used to identify all published molecular time estimates bearing on the divergence of two chosen taxa, such as species, compute summary statistics, and present the results . . . For those interested in published summaries of relationships and divergence times of major groups of organisms (family level and above), see the authoritative synthesis The Timetree of Life.

Here are some examples to get you started: Humans and Chimpanzees diverged 6.3 MYA; Giraffes and Dolphins diverged 58.3 MYA; Cats and Mice diverged 95.2 MYA; and Dogs and Fleas diverged 777.8 MYA. [more inside]
posted by troll on Oct 27, 2011 - 18 comments

Paleo Logic + Evolutionary Psychology ≠ Modesty

Predictors of Being Cheated On: For Women, Predictors of Being Cheated On: For Men, Is Tanning Even Attractive?, The Semiotics of Meat, Sexual Selection Reversal: The Rise of Male Choosiness, Three Ways to Get Academic Journal Papers and Scientific Studies for Free, Big Butts and Breasts: What Sir-Mix-A-Lot Got Wrong About Beauty and Attraction and many more interesting, opinionated, and divisive essays found at Evolvify. [more inside]
posted by Telf on Oct 10, 2011 - 65 comments

My name is LUCA, I live on the ocean floor.

Scientists have come closer to finding the common ancestor of all Earth life. The last common universal ancestor (LUCA) is an idea that goes back to Charles Darwin's On the Origin of Species and whose existence is supported by the fact that all Earth life is based on DNA. But the tantalizing search is getting closer, primarily based on the question, "Which features of the archaea, bacteria and eukaryotes can be traced back to their common ancestor, LUCA?"
posted by Renoroc on Oct 8, 2011 - 34 comments

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