Avery BilloPeriod 6The Salamander’s TaleHow many Rings occur naturally in Nature?In Camp Wolahi, how do the scientists control the species?Is there an exception to the non-interbreeding criterion?Are the Birds referred to differently in the different regions?When did the last known intermediate die out between humans and other species?Is there an ethical problem with viewing the world this way?Salamander:-Central valley in California, Coastal range in west, Sierra Nevada to the east, link up at ends of valley-Genus of salamander(ensatina) can move around the valley, but not across it-individuel salamanders can interbreed with neighbors whose parents might have interbred with neighbors around the ring-Therefore potential gene flow all around the ringStudy Area: Camp Wolahi-there is 2 clearly distinct species of Ensatina, no interbreed, one is marked with yellow and black blotches, other is uniform light brown with no blotches-Non-interbreeding is the recognized criterion for whether 2 populations deserve distinct species names-Hard to treat Ensatina eschscholtzii and ensatina klauberi as separate speciesAnother example of continuous gene flow:GullsIn britain, herring gull and lesser black-backed gull are distinct species, NOT cross breed, so zoologists are justified in giving them different names-follow the population around the globe, the herrings gulls resemble lesser black-backed gulls-legal and ethical principles are based on the separation between humans and other species -We can comfortably visualize gaps between chimpanzees and us, but with intermediates would we still that way?-Because the intermediates are almost always extinct, we can get away with assuming there is a distinct discontinuity between speciesSummary: This article is about how intermediates between species can change the perspective of the whole concept of humans and the view that we are superior and so different from other animals. This relates to our study of evolution, and interbreeding, as well as evolutionary history. We are direct ancestors to fish in a time period, we couldn’t breed with them, but we are linked by ancestral generations. Modern Darwins How did they discover DNA?Is the gene in the different species of finches there, but not expressed, or has it disappeared?(ex. BMP4)How do you find a gene that is expressed for beak shapes of the finches?Was this a mutation?Is there an example in which natural selection can’t explain a trait in an organism?1953 Francis Crick and James Watson found that every organism has a chemical code for its creation inside its cells(DNA) -Finches: Darwin could see their beaks were shaped differently, and made the assumption that they all came from one ancestor-scientists can confirm that the finches did descend from a single ancestral species-DNA confirms the reality of evolution, and it shows at a basic level how it reshapes living thingsArhat Abzhanov and Cliff Tabin pinned down genes responsible for the beak shapes in the Galapagos finches – BMP4 is expressed in the growing jaw of a finch embryo, and makes the beak deeper and wider – Calmodulin is expressed mostly in finches with a long and thin beakAnother ex. Islands off Gulf coast of Florida -Mice with paler coats than mice on the mainland; camo is good for hiding on pale sand, predators eat darker mice, and that leaves the others to breed -Hopi Hoekstra traced the color difference to change of a single letter in a single gene, which lead to cuts in production of pigment in the fur; mutation happened around when islands formed 6,000 years ago-Darwin’s greatest idea: Natural selection is responsible for the variety of traits among related speciesNow people can see natural selection at work, molding and modifying the DNA of genes and their expression to adapt the organism to the environment it lives in.
Summary: This article talks about natural and sexual selection in relation to Darwin, and also the new modern advancements we have made, like discovering DNA, and how the genes can reshape living organisms. This relates to our study of Evolution and how it results in speciation. The Dirty Little Secret Of Cancer ResearchDoes immortal mean that it will never die, as long as it has ideal conditions?Can the public or government sue the company or person who continues to use contaminated/imposter cell lines?Why is HeLa the most used cell line?If the cost of validating cell lines dropped, why do scientists continue not to?Why does NIH not require fingerprinting?What should be included in the checklists?-Kenneth Ain(Thyroid Cancer) owns one of the largest single-physician practices over the country and more than 70 peer-reviewed publications to his name(lot)-Has a repository of 18 immortal cancer cell lines, which were developed by taking cancer tissues from the patients tumors after removal-Labs around the world relied on KAT lines to gain knowledge of cellular changes in thyroid cancer, and to screen drugs that might treat it-June 2007 Ain was told several of his best selling cell lines were not actually thyroid cancer-Really bad because research based of false cell lines would undermine the understanding of different cancers and treatments -Found that 17/18 most popular KAT lines were not thyroid cancer-Found out contamination was due to melanoma and colon cancer, which grow faster-across different fields of cancer research ?+ have been ID as imposters, widely ignored, and lines continue to be used under false identities-Most studied cell line is HeLa, allows researchers to study polio, measles, HPV, HIV and tuberculosis-also the most common cell line contamination, 20% of contamination is due to HeLe-Exposing cell lines cost Walter Nelson-Rees his career, and he was able to make it clear that HeLa is not the only problem-2007 cost of validating cell lines has fallen dramatically, and the power of the testing tech had increasedSTR was increasingly popular, and the chance of two cells coming up with the same STR fingerprinting profile is 1 in 100 million; problem with the sample-NIH did not require fingerprinting for it’s grants, so scientists didn’t have incentive-Today Cell lines known for nearly 50 years to be imposters are still widely used under assumed names-False lines that were Melanoma and passed off as Breast Cancer and Thyroid Cancer were used to develop drugs that were in the early trials-Contamination can happen in every single lab, and Myers thinks the field needs to establish checklistsSummary: This article is about contamination in Cell Lines for Cancer research. This relates to our ongoing study of ethics, because having a contaminated cell line, and knowing it, while still doing research on it like it wasn’t an imposter is unethical. It also relates to when we learned about DNA fingerprinting, because the same method can be used to see if the cell line is contaminated or not.