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A blog from the Consortium for Evolutionary Studies at California State University, Fresno.
Here's another fun weird science story from NPR, about a creature that might be in the dirt in your own backyard:
20100305 Me 03 by Npr
Download now or listen on posterous
Naegleria-NPR.mp3 (1426 KB)
Courtesy of Lillian Fritz-Laylan
Naegleria gruberi grows a pair of flagella when under stress. But unlike a sperm tail, it puts these appendages out front, and swims by breast stroke. The organism is stained to emphasize its anatomy.
If you prefer to read the story rather th........ Read more »
Fritz-Laylin, L., Prochnik, S., Ginger, M., Dacks, J., Carpenter, M., Field, M., Kuo, A., Paredez, A., Chapman, J., & Pham, J. (2010) The Genome of Naegleria gruberi Illuminates Early Eukaryotic Versatility. Cell, 140(5), 631-642. DOI: 10.1016/j.cell.2010.01.032
One trait that shows interesting evolutionary trends is the size of animals. Body size plays a significant role in the most important interactions between animals: competition (for resources or mates) and predation (for both predator and prey). Body size is also, of course, significant for a variety of physiological reasons. It's no surprise, therefore, that biologists spend a lot of time thinking about body size, and have discovered some intriguing patterns. For instance the so-called island ru........ Read more »
G. Grey. (1873) Description of the extinct gigantic bird of prey, Hokioi, by a Maori. Transactions of the New Zealand Institute, 435. info:/
Scofield, R., & Ashwell, K. (2009) Rapid Somatic Expansion Causes the Brain to Lag Behind: The Case of the Brain and Behavior of New Zealand's Haast's Eagle ( ) . Journal of Vertebrate Paleontology, 29(3), 637-649. DOI: 10.1671/039.029.0325
Sereno, P., Tan, L., Brusatte, S., Kriegstein, H., Zhao, X., & Cloward, K. (2009) Tyrannosaurid Skeletal Design First Evolved at Small Body Size. Science. DOI: 10.1126/science.1177428
A couple of interesting examples of the self-correcting nature of Science today:1. It turns out that good ol' Charlie Darwin was wrong about the human appendix! Bollinger and colleagues reported several years ago that this sometime exemplar of vestigial organs is not so useless after all: The human vermiform (“worm-like”) appendix is a 5–10 cm long and 0.5–1 cm wide pouch that extends from the cecum of the large bowel. The architecture of the human appendix is unique among mammals, and ........ Read more »
Randal Bollinger, R., Barbas, A., Bush, E., Lin, S., & Parker, W. (2007) Biofilms in the large bowel suggest an apparent function of the human vermiform appendix. Journal of Theoretical Biology, 249(4), 826-831. DOI: 10.1016/j.jtbi.2007.08.032
SMITH, H., FISHER, R., EVERETT, M., THOMAS, A., RANDAL BOLLINGER, R., & PARKER, W. (2009) Comparative anatomy and phylogenetic distribution of the mammalian cecal appendix. Journal of Evolutionary Biology. DOI: 10.1111/j.1420-9101.2009.01809.x
What, you think you are not left-handed? Just because you favor your right hand to write/eat/pitch that baseball, etc.? Actually, in case you didn't already know this: deep down, at the amino acid level, we are all lefties! Southpaws, each and every one of us! That's just another one of those wonderfully weird arbitrary fact about life on earth! Amino acids, the building blocks of proteins, are fundamental to the structure and function of life as we know it on our planet (which is pretty much ho........ Read more »
Glavin, D. P., & Dworkin, J. P. (2009) Enrichment of the amino acid l-isovaline by aqueous alteration on CI and CM meteorite parent bodies. Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.0811618106
Rebekah Wukits discusses recent findings about ratite evolution for Bio 135.Ratite evolution has been debated for centuries. Some of the earliest evolutionary biologists questioned whether or not ratites had a linear evolution or if the major groups had had independent origins. Richard Owen proposed that living ratites had much more in common with other flight capable groups while being united by the “arrested development of wings unfitting them for flight”. In 1951, two ornithologists, Mayr........ Read more »
J. Harshman, E. L. Braun, M. J. Braun, C. J. Huddleston, R. C. K. Bowie, J. L. Chojnowski, S. J. Hackett, K.-L. Han, R. T. Kimball, B. D. Marks.... (2008) Phylogenomic evidence for multiple losses of flight in ratite birds. Proceedings of the National Academy of Sciences, 105(36), 13462-13467. DOI: 10.1073/pnas.0803242105
Rebecca Freeman submitted this essay for the Evolution class.According to the World Health Organization (WHO), a “hot zone” is an area with >5% prevalence (or incidence) of Multi-Drug Resistant Tuberculosis (MDRtb). Sally M Blower and Tom Chou have been using a mathematical method to track the emergence and evolution of multiple strains of drug resistant tuberculosis, but they have now developed a new, more complex mathematical model. Before this model, there was only a two strain model, ........ Read more »
Sally M Blower, & Tom Chou. (2004) Modeling the emergence of the 'hot zones': tuberculosis and the amplification dynamics of drug resistance. Nature Medicine, 10(10), 1111-1116. DOI: 10.1038/nm1102
Submitted by Christopher Clapp for the Evolution class.The introduction of a known species of rainbow trout into a native population of cutthroat trout and the consequences of their contact within their environments is the focus of this study. The interaction of these two species has resulted in their study of subsequent progeny shows hybridization of the two, and thus a decline of the natural populations of cutthroat trout. The implications of this hybridization will show throughout subsequent ........ Read more »
Denise K. Hawkins, & Chris J. Foote. (1998) Early survival and development of coastal cutthroat trout (Oncorhynchus clarki clarki), steelhead (Oncorhynchus mykiss), and reciprocal hybrids. Canadian Journal of Fisheries and Aquatic Sciences, 55(9), 2097-2104. DOI: 10.1139/cjfas-55-9-2097
Roland A. Knapp, & Kathleen R. Matthews. (2000) Non-Native Fish Introductions and the Decline of the Mountain Yellow-Legged Frog from within Protected Areas. Conservation Biology, 14(2), 428-438. DOI: 10.1046/j.1523-1739.2000.99099.x
J. L. Metcalf, M. R. Siegle, & A. P. Martin. (2008) Hybridization Dynamics between Colorado's Native Cutthroat Trout and Introduced Rainbow Trout. Journal of Heredity, 99(2), 149-156. DOI: 10.1093/jhered/esm118
Rudy Cerda confesses for the Birds & Reptiles class. Elsewhere, Claire Go has blogged about the same study!As much as I like to think that I plan according to future needs, such as time management in order to write papers, study for exams, and even complete this blog, I know I can only operate under pressure. However, when planning for “essential” needs such as food or snacks, I save the best for last or at least hide some away in case I may need or want any later. For example, I’ll al........ Read more »
Submitted by Pedro Garcia for EvolutionBirds, birds, and more birds, with over 10,000 species of birds well known and classified, one can get an array of different colors which would make even the most non-bird lover’s staring in awe. With some species having such intricate combinations of reds, yellows, greens, and blues, (such as the scarlet macaw of South America) one might ask, “Why do they have such vibrant and magnificent plumage?” (or something along those lines). It’s a well know........ Read more »
J. J. Negro, G. R. Bortolotti, J. L. Tella, K. J. Fernie, & D. M. Bird. (1998) Regulation of integumentary colour and plasma carotenoids in American Kestrels consistent with sexual selection theory. Functional Ecology, 12(2), 307-312. DOI: 10.1046/j.1365-2435.1998.00176.x
Submitted by Brandon Williams for the Evolution class.In this article, Carl Woese provides a theory on the early evolution of cells. Woese posits that it is necessary to go beyond classic Darwinian thinking of Vertical Gene Transfer (parent to offspring). He believes that Horizontal Gene Transfer (HGT) played a more crucial role in the early development of cells; that is until each of the three branches of life (Bacteria, Archaea and Eucarya) reached their Darwinian Thresholds. This threshold is........ Read more »
Andrew Mora offers a review of the Biology department seminar by Rachel Mazur.The American Black Bear, Ursus americanus, is currently the only species of bear in the state of California. In a fascinating presentation by Rachel Mazur, pictures and videos were used to depict the beauty of these bears in their natural and not so natural environments; the latter being bears foraging for food in developed areas of the national parks including getting food out of trash cans, cars, etc.According to Maz........ Read more »
R MAZUR, & V SEHER. (2008) Socially learned foraging behaviour in wild black bears, Ursus americanus. Animal Behaviour, 75(4), 1503-1508. DOI: 10.1016/j.anbehav.2007.10.027
Submitted by Cindy Hua for EvolutionMost of us think that evolution in species take several generations to thousands of years to occur. However, how about if I say in one generation’s time there is a significant change in morphology? Jonathan Losos and his team of researchers from Washington University, St. Louis has found a peculiar lizard that is evolving in a tremendous rate. The brown anole, a Caribbean native lizard, spends most of its day hunting on the ground. One of its main predators ........ Read more »
J. B. Losos, T. W. Schoener, R. B. Langerhans, & D. A. Spiller. (2006) Rapid Temporal Reversal in Predator-Driven Natural Selection. Science, 314(5802), 1111-1111. DOI: 10.1126/science.1133584
Jennie Talbot shares her musings following the class discussion last week in Biogeography (Biol 275).In class we discussed the idea that niches are places that supply a particular organism with all of the resources required for it to thrive. The discussion led to questions regarding how much the niche impacted the species and, in turn, how much the species impacted the niche. For example, a plant species may thrive on the side of a mountain because it is here that the plant can find soil with go........ Read more »
Harold C. Urey. (1952) On the Early Chemical History of the Earth and the Origin of Life. Proceedings of the National Academy of Sciences, 38(4), 351-363. DOI: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid
A critique submitted by Brett Moore for the Evolution class.Aquatic macroinvertebrates have received and are continuing to receive considerable amounts of scientific attention. The large amount of diversity within macroinvertebrates allows them to be present in almost all natural freshwater environments (Resh and Rosenberg 1984). The evolutionary adaptations that created the diversity within the group also created the great variety of life histories and physiological requirements, which promote........ Read more »
Andrew J. Boulton. (2003) Parallels and contrasts in the effects of drought on stream macroinvertebrate assemblages. Freshwater Biology, 48(7), 1173-1185. DOI: 10.1046/j.1365-2427.2003.01084.x
J. Bruce Wallace. (1990) Recovery of lotic macroinvertebrate communities from disturbance. Environmental Management, 14(5), 605-620. DOI: 10.1007/BF02394712
File this one under the "who woulda thunk it?", or "why didn't I think of this?" or simply "whaaa...?!" categories! Quick, can you tell which way is north in this picture?Do you think of asking the cow for directions? Why not? For it seems that cow probably knows which way north is!You know, these big dumb-seeming large mammals you pass by every day, these big walking, grazing cheese-producing happy cows dotting the picturesque landscapes of California's grassy hillsdes, or their scrawnier but h........ Read more »
S Begall, J Cerveny, J Neef, O Vojtcch, & H Burda. (2008) Magnetic alignment in grazing and resting cattle and deer. Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.0803650105
Student post submitted by Pritha SinghIn the article “Evolution of Drug Resistance in Mycobacterium tuberculosis: Clinical and Molecular Perspective”, the author Stephen Gillespie describes the clinical circumstances and the molecular mechanisms that are involved in the emergence of drug resistance in tuberculosis (TB). Even after so many years of introduction of very effective drug therapy for TB, the number of people infected worldwide is still increasing due to the development of drug res........ Read more »
Stephen Gillespie. (2002) Evolution of Drug Resistance in Mycobacterium tuberculosis: Clinical and Molecular Perspective. Antimicrobial Agents and Chemotherapy, 46(2), 267-274. info:PMID/11796329
Amanda Scott has a different take on the tool using Chimpanzee story written about by Scott Brown, and seen in this videoToday we know that chimpanzees use tools such as modified sticks and rocks to assist in their feeding. Rocks are used to crack open shells of nuts or seeds. Today fossil remains in Tai National Park have been identified as chimpanzee tools. Physical characteristics that distinguish them as being products of thrusting or percussion separate them from the other rocks in the area........ Read more »
J Mercader, H Barton, J Gillespie, J Harris, S Kuhn, R Tyler, & C Boesch. (2007) 4,300-Year-old chimpanzee sites and the origins of percussive stone technology. Proceedings of the National Academy of Sciences, 104(9), 3043-3048. DOI: 10.1073/pnas.0607909104
Student post submitted by Philip LocktonThis article is a good example of the effects of evolution on current day pests and parasites. In regards to pest management, pesticides and insecticides have been developed in the last century to deter the effects of parasitic damage. In agriculture, insecticide use is critical in managing and controlling both crop and livestock production. The development of chemical insecticides has allowed humans to produce more reliable agricultural goods with greater........ Read more »
J McKenzie, & P Batterham. (1998) Predicting insecticide resistance: mutagenesis, selection and response. Philosophical Transactions of the Royal Society B: Biological Sciences, 353(1376), 1729-1734. DOI: 10.1098/rstb.1998.0325
Student post submitted by Darin Alexander.
When we think of invading exotic species you already have a negitive view in your mind. There is a high rate of negative publicity on exotic species. They are thought to be destructive, and can cause large amounts of stress and possible extinction of native species. This is a true statement when it comes to terrestrial or aquatic species, but what about marine? In this article John Briggs discusses the benefits, yes benefits, invasive species can have o........ Read more »
John Briggs. (2007) Marine biogeography and ecology: invasions and introductions. Journal of Biogeography, 34(2), 193-198. DOI: 10.1111/j.1365-2699.2006.01632.x
[Student post submitted by Swapna Medichetti]
A group of researchers from Israel conducted an interesting study on human subjects and tried to provide evidence for a signature of facial expressions that is supposedly unique within a family. Before this, many studies relating to this have been done on humans. These studies show proof of facial expressions being heritable in an individual while some focus on how different facial expressions are among individuals. But there have been no reports of ........ Read more »
G Peleg, G Katzir, O Peleg, M Kamara, L Brodsky, H Hel-Or, D Keren, & E Nevo. (2006) From the Cover: Hereditary family signature of facial expression. Proceedings of the National Academy of Sciences, 103(43), 15921-15926. DOI: 10.1073/pnas.0607551103
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