tema 8. evidences of evolution

EVIDENCE OF EVOLUTION

COMPARATIVE ANATOMY1. HOMOLOGOUS STRUCTURES

2. ANALOGOUS STRUCTURES

SUMMARAZING

Structures in different species having the same appearance or function

Structures derived from a common ancestor with different function

3. VESTIGIAL STRUCTURES

4. CONVERGENT EVOLUTION

BIOGEOGRAPHIC EVIDENCES

BIOCHEMICAL EVIDENCES1. The GENETIC CODE is the same in almost all organisms.Over the ages, the genetic code has passed unchanged (or nearly so) from parent to offspring.

The similarity shows a probable common ancestor for all life on Earth.

BIOCHEMICAL EVIDENCES

Number of differences from human hemoglobin

45

167

8

27

125

2. AMINO ACID SEQUENCING, similar genes

BIOCHEMICAL EVIDENCES3. Vestigial Genes (prediction)

Linked to regulation of genes expresion.

* Genes that have lost their protein-coding ability or are otherwise no longer expressed in the cell

Ex. GLO (Vitamin C from glucose) Primate, bats fruit eater and guinea pig. Accumulation of multiple mutations

30.000 genes 2.000 pseudogenes*

Retrovirus DNA Sense of smell, olfactory receptor (1.000 vs. 400/800) Rats, people,dolphins,

EMBRYOLOGYCAL EVIDENCES

1. Serial structures (e.g., segments, limbs) are usually identical in the embryo, but specialized and diverged in the adult.

Haeckel's diagrams

Phylogenesis is the mechanical cause of ontogenesis

EMBRYOLOGYCAL EVIDENCES2. BRANCHIAL ARCHES

FOSSIL RECORD1. The earliest forms of life are simplies than latest

FOSSIL RECORD

2. Transitional fossils

SPECIATIONFactors that contribute to speciation:• Allopatric speciation• Peripatric speciation• Parapatric speciation• Sympatric speciation

REFERENCES CHARLES DARWIN & EVOLUTION by Christ's College, Cambridgehttp://darwin200.christs.cam.ac.uk/pages/

DARWIN EL PADRE DE LA EVOLUCIÓN en el diario El Mundohttp://www.elmundo.es/especiales/2009/02/ciencia/darwin/

STATED CLEARLY Youtube channelhttps://www.youtube.com/channel/UC_cznB5YZZmvAmeq7Y3EriQ• What is Evolution? • What is Natural Selection? • What is the Evidence for Evolution?