evidence of evolution palaeontology biogeography comparative anatomy comparative embryology...
TRANSCRIPT
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 animalso Fossils support the theory of evolution as they:
o Show changes in life forms over timeo Give snapshots of life on earth at various timeso Trace movement
o Transitional forms of fossils support the theory of evolution as they:o Displays how natural selection has taken placeo Shows mutation due to the environmental selective pressureso 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 DriftA 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 DNAo 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.