100 likes | 235 Views
5.3 Evidence of Evolution from Biology . Evidence from Anatomy. Homologous features Features with similar structures but different functions Ex. Forelimbs of a bird, whale horse and human. Evidence from Anatomy. Analogous features
E N D
Evidence from Anatomy • Homologous features • Features with similar structures but different functions • Ex. Forelimbs of a bird, whale horse and human
Evidence from Anatomy • Analogous features • Features that are similar in appearance and function, but do not appear to have the same evolutionary origin • Ex. Bird’s wing vs. Insect wing
Vestigial Features and Anatomical Oddities • Evolutionary relationship among species is also evidenced in embryonic development • Human embryos possess a tail and gill slits (chicken/fish embryos) • http://www.mdpatrick.com/wp-content/uploads/2010/12/embryo-compare.jpg • Form rudimentary tail bone and bones of the inner ear • http://funstuffcafe.com/wp-content/uploads/2010/12/C0025531-Human_baby_with_a_tail-SPL.jpg
Vestigial Features and Anatomical Oddities • Vestigial features: rudimentary structures with no useful function • Once served a purpose/function • Ex. Whales/snakes- vestigial hip and leg bones • Evidence that suggests they evolved from ancestors that walked on 4 limbs • http://io9.com/5829687/10-vestigial-traits-you-didnt-know-you-had
Evidence from Biochemistry • Proteins- component of body structures such as muscle cells and skin cells • Are long chain amino acids • Each type of protein has a certain number and sequence of amino acids
Evidence from Biochemistry • Studies suggest that, over time, similar proteins in different species become increasingly different in terms of their amino acid sequence • Ex. Hemoglobin- CO2 carrying protein in all vertebrates (backbone) • Sequence varies from species to species (Macaque and lamprey)
Evidence from Biochemistry • DNA- (deoxynucleic acid)- the molecule that makes up genetic material • Each DNA molecule contains many different genes • A segment of DNA that performs a specific function such as coding for a particular protein • Made up of 4 nucleic acids • G- Guanine • C- Cytosine • A- Adenine • T- Thymine
Evidence from Biochemistry • DNA sequences from different species that code for the same protein vary in the number and order of the nucleotides • Homologous/vestigial genes exist • Ex. Humans posses a defective set of genes that would allow us to make our own vitamin C
Evidence from Artificial Selection • Artificial selection- the process of humans selecting and breeding individuals with desired traits