Evidence of Evolution Palaeontology Biogeography Comparative Anatomy Comparative Embryology Comparative DNA By: Samantha Assaf and Erin King

Palaeontology o Palaeontology is the study of fossil plants and animals o Fossils support the theory of evolution as they: o Show changes in life forms over time o Give snapshots of life on earth at various times o Trace movement o Transitional forms of fossils support the theory of evolution as they: o Displays how natural selection has taken place o Shows mutation due to the environmental selective pressures o Allows scientists to compare and contrasts organisms at different times Fossil – remnant of once living organism, either part of organism or a trace it left. Transitional Forms – fossils which have characteristics of two different groups of organisms that exist today, showing the evolution of the same original single cell organism.

Biogeography o Biogeography is the study of living things in relation to geographical regions o Darwin and Wallace used biogeography as evidence of evolution. o Biogeography support the theory of evolution as they: o prove that species living in the same area were more similar to each other than to species living in similar habitats far apart o shows that species evolved due to the selective pressure in their own habitats Example: Continental Drift A single species of flightless birds existed on Pangaea, but when continents split, that different birds evolved to suit new climates, creating different species in each area.

Comparative Anatomy o Anatomy of different species can be compared to look for evidence of evolution which would come from a common ancestor. o Due to evolution, different species of organisms have similar body anatomy as they all originated from the same single cell organism. o Comparative Anatomy supports the theory of evolution as it shows: o Homologous structures are structure that have the same origin but not necessarily same form or same function. o Vestigial structures are structures that an organism no longer uses but still has as a part of its body. Homologous Structures Vestigial Structures

Comparative Embryology o Embryos of different living things can be extremely similar. o Comparative Embryology supports the theory of evolution as: o The embryos of many species such as fish, humans, birds, turtles and rabbits all look much like the same. o It shows that they have all come from an original single cell organism which is the common ancestor o It gives proof that organisms have inherited common stages of embryonic development

Comparative DNA o All living things have DNA o Comparative DNA supports the theory of evolution as: o The more closely related species are, the more common their DNA sequencing is o When two new species evolve from a common ancestor their DNA slowly changes and becomes different due to meiosis and mutation o The number of differences is proportional to the time since they separated as evolution occurs over time. Humans DNA is most similar to that of a chimpanzees.