1 / 17

Testing Biological Relatedness: DNA Similarity and Evolutionary Patterns

Explore how DNA similarity can be used to test hypotheses of biological relatedness and analyze evolutionary patterns. Discover the connection between DNA, common ancestry, and the prediction of species in the fossil record.

fitzgeraldr
Download Presentation

Testing Biological Relatedness: DNA Similarity and Evolutionary Patterns

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Post-Darwinian Facts I. Physics II. Geology/Paleontology III. Genetics

  2. III. Genetics obviously, the most direct way to test hypotheses of biological relatedness is to compare DNA.

  3. III. Genetics obviously, the most direct way to test hypotheses of biological relatedness is to compare DNA. - DNA comes ONLY from ancestors, and we now how it is replicated and passed to offspring.

  4. III. Genetics obviously, the most direct way to test hypotheses of biological relatedness is to compare DNA. - DNA comes ONLY from ancestors, and we now how it is replicated and passed to offspring. - DNA similarity implies a common source of this DNA – common ancestry. - within a species – paternity tests

  5. III. Genetics obviously, the most direct way to test hypotheses of biological relatedness is to compare DNA. - DNA comes ONLY from ancestors, and we now how it is replicated and passed to offspring. - DNA similarity implies a common source of this DNA – common ancestry. - within a species – paternity tests - Patterns between species? 1. GROSS CHROMOSOMAL SIMILARITIES

  6. 2. SEQUENCE ANALYSES - Human and chimp DNA is 98.4% similar in nitrogenous base sequence.

  7. 2. SEQUENCE ANALYSES - Human and chimp DNA is 98.4% similar in nitrogenous base sequence. - well, we are similar (mammals, primates, etc.) So, to be similar, don’t we need similar recipes?

  8. 2. SEQUENCE ANALYSES - Human and chimp DNA is 98.4% similar in nitrogenous base sequence. - well, we are similar (mammals, primates, etc.) So, to be similar, don’t we need similar recipes? - But, only 10% of the genome is a recipe. Even the 90% that does not code for protein, that is random sequence, still shows this similarity. Even non-functional DNA is similar, so functional similarity (ie., ANALOGY) can’t be the answer…the similarity is HOMOLOGOUS.

  9. 3. Corroborating Independent Tests of Evolution - We build “family trees” with paleontology

  10. 3. Corroborating Independent Tests of Evolution - We build “family trees” with paleontology - We build “family trees” with genetic similarity.

  11. 3. Corroborating Independent Tests of Evolution - We build “family trees” with paleontology - We build “family trees” with genetic similarity. If both these patterns are caused by common ancestry (and evolution), then they should be the SAME pattern.

  12. 3. Corroborating Independent Tests of Evolution Testing Evolutionary Theory (yet again) IF species are descended from common ancestors (like people in a family), and IF we know the rate of genetic change (mutation), THEN we should be able to compare genetic similarity and predict where in the fossil record common ancestors should be.

  13. 3. Corroborating Independent Tests of Evolution

  14. 3. Corroborating Independent Tests of Evolution

  15. 3. Corroborating Independent Tests of Evolution

  16. 4. Conclusions - We can compare the DNA in existing species and predict where, in the sedimentary layers of the Earth’s crust, a third DIFFERENT species should be. - No explanation other than evolution predicts and explains this ability. Evolution by Common Descent is a tested theory.

More Related