Introduction 1. INTRODUCTION A typical ichthyosaur looks like this (see note for derivation and pronunciation of "ichthyosaur", as well as its usage in this page). Yes, just like a fish. The strange thing is that they were not fish at all: they were reptiles like lizards, snakes, and crocodiles. You can easily tell this by looking at the skull and fins. A similar case is known for mammals too: think about dolphins and whales.
Instructional Multimedia Welcome to the Department of Biology's instructional multimedia page. This site showcases educational material that has been developed for use in departmental courses. If this is your first visit, we suggest checking to see that you have the appropriate plugins installed on your computer. Once you have the appropriate plugins you may proceed to the instructional multimedia. If you have any questions, check the FAQ page and if you can't find the answer there, you can email us. Check out some of the video work done in our lab
Ancestral Lines Evolutionary biologists use a cladogram, the treelike diagram of evolutionary branches or clades, to organize species into lines of evolutionary descent across time. Biologists use three types of evidence to deduce evolutionary connections: genetics, morphology, and geologic dating. (Behavior, normally a key part of evolutionary studies, can only be inferred in extinct species — for example, by examining the ecology in which the species flourished and the species adaptations for eating and locomotion.) Analyses of primate fossils and the genetic relatedness of living primates converge to the conclusion that humans and chimpanzees branched from a common ancestor about 7 million years ago. DNA recovered from several uncontaminated Neanderthalensis fossils indicated that modern humans and extinct neanderthals diverged about 400,000 years ago; but more recent studies show that they must have interbred within Europe or the Middle East since then.
Building Bodies | Becoming Human Primate Bipedalism: Understanding Standing Up <p>This site requires Javascript, please update your browser...</p><p></p> Anthropologists and evolutionary biologists agree that upright posture and the subsequent ability to walk on two legs was a crucial major adaptation associated with the divergence of the human lineage from a common ancestor with the African apes. Efficient upright walking required numerous changes in the anatomy of the limbs and pelvis and we are the result of the variations and selection pressures that forged this new ability. Main Concepts Human evolution is marked by a mosaic pattern. Assessible Objectives Students will... identify key anatomical similarities and differences between the great apes and humans.infer likely anatomical features in ancient human ancestors.list principal anatomical changes in primates necessary for adaptation to fully bipedal locomotion.sequence particular anatomical features in hominids as part of a series of broader evolutionary trends.
UNKNOWN TERRITORIES What did our ancestors look like? Hair and eye color can be determined for ancient human remains A new method of establishing hair and eye colour from modern forensic samples can also be used to identify details from ancient human remains, finds a new study published in BioMed Central's open access journal Investigative Genetics. The HIrisPlex DNA analysis system was able to reconstruct hair and eye colour from teeth up to 800 years old, including the Polish General Wladyslaw Sikorski (1881 to 1943) confirming his blue eyes and blond hair. A team of researchers from Poland and the Netherlands, who recently developed the HIrisPlex system for forensic analysis, have now shown that this system is sufficiently robust to successfully work on older and more degraded samples from human remains such as teeth and bones. The system looks at 24 DNA polymorphisms (naturally occurring variations) which can be used to predict eye and hair colour.
Marvin and Milo Explore physics the exciting way, by trying out a simple and fun experiment. This month, Leaning Tower Don't forget to check back next month for the next edition... Spinning eggs Print this page What you need a raw egga hard-boiled egg Instructions First spin the hard-boiled egg. Results & explanation The egg starts spinning! Share: The folowing links are external
Chromosome Connection | Becoming Human Comparison of Human and Ape Chromosomes <p>This site requires Javascript, please update your browser...</p><p></p> Students are taken on a chromosome comparison "adventure", in which the banding patterns are compared on the chromosomes of humans and apes. Degrees of similarities, and some causes of their differences are explored. Inferences about relationships based on those similarities are also examined in a compelling way. Main Concepts The degree of chromosome similarity between two species indicates the degree of their biological relationship. Assessable Objectives Students will... actively engage in the careful analysis of chromosome banding patterns.identify examples of inversion in homologous chromosomes.demonstrate their understanding that degrees of similarities in chromosomes correspond to degrees of evolutionary relationship.associate degrees of similarity with relative timing of evolutionary divergence. Teaching Strategy & Preparation Preparation Directions Assessment Bibliography
Convergent Evolution: Hyenas Offer Clues To The Human Past : 13.7: Cosmos And Culture When anthropologists work to reconstruct the lives of our own ancestors we bring together multiple sources of information. We look at fossils and material culture, such as ancient tool technologies. We even look at animals alive today whose behavioral patterns might provide clues to our past. When it comes to these animal models, we think first of apes. So why not look for clues from more distant animal kin? hide captionSpotted hyena cubs socialize at their communal den in the Maasai Mara National Reserve, Kenya Courtesy of Deanna Russell Spotted hyena cubs socialize at their communal den in the Maasai Mara National Reserve, Kenya I like Smith et al.' So let's unpack all this. As the Current Anthropology article explains, about 85 percent of terrestrial mammalian carnivores are solitary outside of mating and parental-care contexts. They're more socially complex than carnivores like wolves, lions and wild dogs. But exactly what is it that hyenas are doing that apes aren't doing?
Unique ancient spider attack preserved in amber Researchers have found what they say is the only fossil ever discovered of a spider attack on prey caught in its web -- a 100 million-year-old snapshot of an engagement frozen in time. The extraordinarily rare fossils are in a piece of amber that preserved this event in remarkable detail, an action that took place in the Hukawng Valley of Myanmar in the Early Cretaceous between 97-110 million years ago, almost certainly with dinosaurs wandering nearby. Aside from showing the first and only fossil evidence of a spider attacking prey in its web, the piece of amber also contains the body of a male spider in the same web. This provides the oldest evidence of social behavior in spiders, which still exists in some species but is fairly rare. Most spiders have solitary, often cannibalistic lives, and males will not hesitate to attack immature species in the same web. "This was a male wasp that suddenly found itself trapped in a spider web," Poinar said.
Human Evolution & Archaeology The Tree of Life If you want a hardcopy of this poster, you can either (1) download the PDF file here for free and take it to a print shop (Kinkos will work) and get it printed as a large poster (it prints 24" x 48"), or (2) buy it online at Zazzle.com (click here to jump to the poster). The words in the image above may look a bit blurry because this web page is displaying a compressed JPEG image on this web site (to improve download time). If you make a print from the PDF file (or zazzle) all the words and lines will be crisp and clear. I created the poster with the Xara Xtreme drawing program. Keywords: Tree of Life, evolution, cladogram, cladistics, darwin, phylogenetic tree, phylogenetics, evolutionary tree, darwin, poster. Permission to copy and modify this illustration is given under the Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License (
The Origin and Evolution of Life the basic outline of the origin of life is believed to be: formation of earth 4.6 bya formation of monomers (simple amino acids, sugars, etc) formation of polymers (proteinoids, nucleic acids, etc) lipid synthesis for membranes (phospholipids) formation of a protobiont RNA is believed to be the first information molecule; DNA likely came later 3 different scenarios exist regarding how life began: tidal pools, with drying and rewetting, offered an excellent medium to accumulate monomers and polymerize them; then form coascervates which would have been precursors of protobionts panspermia - a cosmic origin of life where organisms from other planets seeded earth via a meteor undersea thermal vents, which provide the necessary energy and catalysts for life's origins one scenario: required 60°C heat, produced polymers of 100 amino acids (MW > 10,000) this may have occurred in tidal pools where periodic drying occurred adding polymers to water forms larger structures an early life form would have required: