Evolution and the Origin of Life

Lecture 2

Charles Darwin title

naturalist

Charles Darwin theory credit

natural selection

Location of Charles Darwin main observatio

Galapagos Island

Charles Darwin animal of study

finches

Darwin’s finches trait studied

beaks

Result of changes over time within finches

Speciation

Darwin’s main idea

natural selection happens through preservation of favorable variation and rejection of injurious variation

Convergent Evolution

two distantly unrelated animals evolve similar traits through similar selection pressures

Artificial Selection

instead of nature deciding favorable traits, human select for them

Source of variation

mutations

Relevant types of Mutations

Substitution, Deletion, Insertion, Inversions

Mutations End Result

Either nothing or cancer most of the time, sometimes useful adaptation

Why do small animals live less?

Less proofreading mechanisms result in more mutations

Mutations cause

Bad DNA cloning or UV Proton damage

Teleology

the philosophical idea that things, events, and natural phenomena are best understood by their purpose, goal, or final end rather than just their cause

Richard Dawkins book and idea

Selfish gene

No long term goal of evolution

Memetic Evolution

a theory of cultural change proposing that ideas, behaviors, and skills—called memes—replicate, mutate, and undergo natural selection much like biological genes

Natural Selection in Humans

natural selection has slowed because humans are more often in artifical envionrments

Main differientater between humans and other species

Ability to represent ideas in our heads

What type of evolution is memetic evolution?

Behavrioal

Behavioral Evolution Example

Moving places to switch temperature

Physical Evolution Example

Shivering/Sweating to adjust body temperature

Creation of the moon

magma shot up and the gravity caused it to turn into moon (it is made of the same “stuff” as the earth)

Calcium

rocks tend to float to the surface - the coloration of the moon depicts heavier rocks being sunk in and calcium deposits higher up

Origin of water on Earth

Comet made of ice

Formation of first RNA

prebiotically plausible molecules can spontaneously turn into RNA under the right conditions in a process called unified synthesis

RNA natural selection

RNA can self replicate and RNA that self replicates faster or “better” would be selected for (first example of natural selection)

RNA neutralization

neutralization stops RNA replication (often neutralized by calcium ions that dissolve in water)

Components of Life (in theory)

Nucleic Acids, Proteins, Spontaneous membranes (viruses also have these components but are not considered life because they need a host to replicate)