7 - Evolution PDF (Notes)

7 - Evolution Notes Status Done Lab Notes Status / ORGANIC EVOLUTION → stable long-term change in the physical and/or behavioral features of populations Jean Baptiste De Lamarck 1. No exti...

7 - Evolution Notes Status Done Lab Notes Status / ORGANIC EVOLUTION → stable long-term change in the physical and/or behavioral features of populations Jean Baptiste De Lamarck 1. No extinctions 2. Individuals bound to ameliorate, improving complexity and performance of populations → use will develop the organ, disuse will waste it - improvements passed down (ex. giraffe stretches neck) 3. Species do not exist as discrete units, individuals transform under pressure from environment Charles Darwin 1. New species appear thanks to natural selection → no implications of improvement, progress or purpose - random variability favors the fittest (ex. giraffe with a randomly longer neck will eat more) Variability must work randomly, be high and work fast Hereditariness of variability (genes) must be complete and allow full transmission of information 7 - Evolution 1  Evolution takes time and patience, cannot be replicated in lab. Proofs may arise from: Adaptation → fitness of organism to perform and survive in the environment he has to live in - goal achieved with adaptive skills (body parts, color and pattern, mimicry and camouflage...) and behavioural adaptations (inherited like hibernation and learned like communication/finding food) → CREATIONIST: intelligent design, no evolution occurred, perfect features since the beginning → EVOLUTIONIST: adaptations develop randomly, natural selection, efficient remains and the others disappear, accounts for homologies and failed adaptations Morphology and homology → organisms of same taxonomic group have similar structures for many parts of their bodies (homologies) Mammalia, similar development in womb → ⚠️analogous: similar functions but evolved separately: NO common ancestor (convergent evolution) 7 - Evolution 2  Vestigia → body improvements but some limits are defined by the genetic program first provided by their ancestors, which prevents the accomplishment of the “perfect adaptations” (ex. remains of feet/paws in whales and snakes) Biogeography → distribution of living organisms across the planet and the factors that influence their patterns, such as geography, climate, and evolutionary history - different adaptations based on environment Embryology → within a large group of animals, primitive traits appear in the earliest stages of embryo development 7 - Evolution 3  Paleontology → Paleontology provides evidence for evolution and its mode and tempo, but the fossil record is incomplete. The lack of "missing links" is explained by the theory of punctuated equilibrium, which contrasts with Darwin's gradualism, suggesting that evolution occurs in rapid bursts followed by long periods of stasis. 7 - Evolution 4