EvolutionEnvironmental Biology

Who was Charles Darwin?

• Father of evolution• Went to the

Galapagos Islands in South America

• Wrote On the Origins of Species when he came back

• Went against religious beliefs

• Suffered from making findings

• 25 years later, people honored and believed his works and theories

Who was Charles Lyell?

• American geologist• Studied how

the Earth changes over the years

• Ex: mountains, river, etc

Who was Thomas

Malthus?• Sociologist, scientist and

politician• Observed why weren’t

available resources used up?

• Disease, starvation, and natural disasters, all wiped out a large chunk of the population

• He wanted to know why some people lived and some died

• He believed in survival of the fittest!• Wealthy white males were

the “fittest”

Who was Alfred

Wallace?• British man, did his

research many years after Darwin

• Studied in South America and Asia

• 1858 – send Darwin a manuscript and they both had the same conclusion

• Darwin contacted Wallace• They published

articles separately and together

What were Darwin’s Two Main Points?

• If non-living things changed over time, why cant living things change too?1. Descent with

Modification – due to the build of mutations over million of years, new organisms form• New species evolved

2. Natural Selection - nature chooses the more desirable traits to pass to their offspring (beneficial mutations)

What is a fossil?

• The remains of a previously existing creature from many years ago

What is a fossil record?

• Time line of when organisms existed in relation to other organisms• 2 ways to determine how old

something is:

1. Relative dating – “this is older/younger than that” based on position without a timeframe

2. Absolute dating/carbon dating – directs to a specific time period more than relative dating does

• Half life – the amount of time it takes for half an element to break down and disappear

• Ex: carbon’s half life is 5730

What does extinct mean?

• When the last of the species dies and the living things in non existent

What are Homologous Structures?

• Look the same but do different things

• Ex: cat’s front and human’s hand

• This suggests a common ancestor branching off to different species

What are Analogous Structures

• Look different but do the same thing (opposite of homologous pairs)

• Ex: birds, butterflies, and bats all have wings but don’t look alike

• This does not a common ancestor but have a similar path

What is Vestigial

Structures?• Structure in the

body that has been used once in the past but is no longer being used in current time

• Ex: appendix, eye brows and tail bone in humans

What is variation?

• The differences within 1 type in natural or excepted differences

• Ex: size and height

What is Natural vs. Artificial Selection?

• Nature selects more desirable vs. selection in organisms to help or not help living things

• Ex: Teacup poodles• Bulldogs born by C-

section

What are Pesticides and Antibiotics?

• Natural selection in action

• Overuse in antibiotics will cause medications to stop working• Organisms that adapt them

are called natural variation• Bacteria changes when in

different environments and has natural variation

• Pesticides are similar to bacteria• Farmers put them on their

crops – some bugs live and some will die

What are speciation?• Decent with

medication – when new species from because of mutations

What is geographic isolation?

• A weakness to evolve or be created

• Setting makes it harder to produce offspring

• Can be a form of reproductive isolation

What is reproductive

isolation?• Two individuals not

having a similar reproductive cycle

• Able to breed but decide not to

• Ex: skunks

What is a genetic drift?

• The undertaking or alteration in genes from each generation

• Ex: Swedish people mainly have blue eyes

• If a brown eye was added to the population, the eye colors would shift

What is a bottleneck?• When a disease

or natural disaster happens• Usually wipes out

a large amount of the population

• Makes a smaller gene pool

• Genes are lost forever

• Ex: Beads in a bottle – stuck at the bottom

What is the founder effect?

• The people that are give will be the only ones to give genes to their future offspring

What is adaptive

radiation?• Life will always

be found even in the most extreme areas

• If something can live, something will live

• Ex: Hawaii/ albatross bird

• Nature wants to fill – hates a vacuum

What is a cost-benefit

analysis?• Measuring pros

and cons to figure out the next step in action

• Ex: Going to a party – getting grounded or being popular?

What is a gene pool?

• All of the genes in the entire population

What is gradualism?• Gradually,

mutations and changes will happen and organisms will evolve at a slow pace

What is punctuated equilibrium?

• The theory that organisms stay the same for a long time, then changes for a short about of time due to the environment

• Organisms quickly change and then remain the same for a long time (repeats the process)

• Ends when gradualism is reached

What is co-evolution?

• Many species that evolve together – change over time

• Ex: Hummingbird and flower makes nectar – the longer the flower gets the longer the beak gets

What is parallel

evolution?• Organisms the

evolve on a pathway that is parallel but don’t have to have a common ancestor

• Ex: Fish and whale – similar body that is able to move through water but they aren’t related (evolved in a similar way)

What is divergent evolution?

• Organisms that have a similar ancestor and evolve together at a certain point • They branch and

develop• Split in different

directions

What is convergent evolution?

• Very similar to parallel evolution

• Organisms develop on separate paths• Through mutations

now have a common ancestor

• Converged

What were the first organisms

on Earth?• They were anaerobic –

didn't’t need oxygen• Able to make their

own food – autotrophs• Gave off oxygen for

millions of years• They became more

complex, Multicellular, and then were able to breath oxygen

What is the Endosymbiotic

theory?• Hypothesis• Mitochondria and

chloroplasts were once free-living

• They combined with a simple cell and were helped from the relationship

• Mutualistic relationship over time became dependent • Able to use each other to

survive

Who was Miller and

Urey?• Theory of life

• Miller’s flask

• Made experiments and concluded that the surroundings in the atmosphere, it was likely to create “the building blocks of live”• Primordial soup