Evidence for evolution #4 Flashcards
Evidence for evolution
- Shared common ancestry
- Paleontology (historical events inferred from fossils)
- Embryology
- Geographic distribution of species (biogeography)
- Genetics
- Comparative anatomy
- Biochemistry
- Molecular biology
- Phylogenetic studies
What is the evidence for shared common ancestry?
All living things share the genetic code, machinery of replication and protein synthesis, basic metabolic reactions, and the use of l optical isomers of amino acids as building blocks for proteins. Paleontology, embryology, geographic distribution of species, genetics, comparative anatomy, biochemistry, molecular biology, and phylogenetic studies also provide evidence for shared common ancestry.
What is biogeography and how does it support the theory of evolution?
Biogeography is the geographic distribution of organisms. It supports the theory of evolution by explaining why current species distributions make sense if species have sites or regions of origin, they achieve broader distributions via dispersal, and they become modified post-dispersal, giving rise to descendant species. Major biogeographic regions contain characteristic taxa and are driven by Earth’s history, which can explain barriers to migration, defined areas with similar organisms within and different (unrelated) organisms between, and why organisms on islands tend to be capable of long-distance dispersal.
What is biogeography?
Biogeography is the study of the geographic distribution of organisms.
What are some observed biogeographic patterns?
pecies have regions of origin, achieve broader distributions via dispersal, and become modified post-dispersal, giving rise to descendant species. Major biogeographic regions contain characteristic taxa. Barriers to migration result in defined areas with similar organisms within and different (unrelated) organisms between. Organisms on islands tend to be capable of long-distance dispersal. Most island species are clearly related to species on the nearest mainland.
What are some factors that can contribute to biogeographic patterns?
Extinction, dispersal, vicariance, relative range sizes of selfers vs. outcrossers, and ecological factors such as temperature, rainfall, and plant productivity.
What is homology?
Homology is the similarity of structures despite differences in function, where characteristics of organisms are modified from those of their ancestors.
What are some examples of homologous structures?
he forelimbs of tetrapod vertebrates and human embryos briefly having branchial pouches similar to gill slits of fish embryos are examples of homologous structures.
What are vestigial structures?
Vestigial structures are structures displayed in almost every species that served a function in the species’ ancestors but no longer do.
What is the fossil record?
The fossil record is the collection of all known fossils, which is incomplete.
What are some limitations of the fossil record?
The record is incomplete because it requires hard body parts, humid environments decay too rapidly, sediments vary over time, fossil-bearing sediments must solidify into rock, persist through time, then be exposed and found, evolutionary changes may not have occurred at the sites where fossils exist.
What is the rationale for using model organisms?
Common ancestry provides the rationale for using model organisms, as genomes of most organisms have similar elements.
What are some examples of model organisms?
Mouse, frog, mustard plant, roundworm, fruit fly, yeast, and zebrafish are examples of model organisms.
What is observable evolution?
Observable evolution is when new advantageous mutations are observed to arise during experimental evolution, such as antibiotic/pesticide resistance.
