I choose to live

Classified in Biology

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Evolution: it happens because of mutations. Individuals don't change, they pass the changes to their offsprings. Population change.

Alfred Russell Wallace: was a naturalist who go the same mechanism as Darwin's: the natural selection. They never met, Wallace was very far from Darwin's son so he died. They communicated by letters. He wasn't recognized as the same time as Darwin due to several factors: he made a mistake, he thought God created our soul and brain. Also he didn't have as many proofs as Darwin and published his ideas later.

Charles Darwin: He made the theory of natural selection (evolution already existed). He went on a 5 year trip to the Galapagos Islands as a naturalist where he found finches. Many years later, he wrote a book about natural selection: those that successfully adapted to meet the changing needs of their natural habitat thrive and reproduce, while the others die off. There were some ideas before him: Fixism (evolution never happen) and Creationism (all nature was born from God)


Buffon: he said that organisms degenerate from their original form created by God, and he was the first one to propose that organisms change

Lamark: he developed ''transformisme'', the traits acquired during life time are passed down to offspring. He also said that evolution was progressive (from simple organism to complex ones) at the contrary of Buffon.

George Cuvier: he was a naturalist who defended fixism, he thought fossils came from living things that were extinct long time ago due to catastrophes, this is called Catastrophism. 

Carl Linnaeus: He created the Binomial system, used till nowadays as a way to classify species. The first name is a general characteristic, the second name is a specific characteristic. For a new animal, 1st you decide it's kingdom, second it's class.


Anatomical and morphological evidence:

-types of structure: homologous structures: are structures with different functions but with the same origin. It proves divergent evolution. (bat wings and human arms)

analogous: are structures with the same function but don't come from a common ancestor. It proves convergent evolution(bat wings and butterfly wings)

vestigial: are structures that tend to disappear because they aren't useful anymore. (a pelvis bone in a snake)

Fossil evidence:

Paleontology: it's the science that studies fossils. Fossils are the remains of activities or of the bodies of very ancient organisms. Most of fossils remains are incomplete because soft parts decompose, hard ones can break and be moved.

     Steps: 1- the soft tissue that exists during life decays leaving behind only the hard parts.  2- hard parts may be transported  and broken.  3 hard tissues become buried and altered.

Fossilization tell us that should have been millions of dinosaurs on Earth. Fossils prove that there have been changes in living things over time. Fossils show organisms that existed in the past and that are different from nowadays organisms, so species change over time. Fossils of organisms that are intermediates between two great groups of living things serve as confirmation of the link between them.

Embryological evidence: when embryos of different species are similar it means that there is an evolutionary relationship between them. Protosomes rae primitive invertebrates while deuterostomes include chordates and echinoderms. The blastpore in protostomes are developed into a mouth wile the blastopore in deuterostomes is developed into an anal opening.

Biogeographical evidence: as time passed, isolated groups of animals evolved in different ways, creating new species.

Divergent evolution: closely related species adapted to different environments

Convergent: species that aren't related may look alike if they live in similar environments.

Molecular evidence: higher the molecular similarities two groups of organisms, the close their evolutionary relationships are.Clorophyl: found in every green plant.     Haemoglobin: found in vertebrate's blood

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