Understanding Genetics and Evolutionary Theory

Natural Selection

Darwin's theory explaining survival of the fittest.

Darwin's Theory

Organisms born with the best adaptations survive and pass on their traits to offspring. Organisms without these adaptations die and do not reproduce. Over time, the population changes as more organisms inherit the adaptation.

Gradual Acceptance of Darwin theory

-theory challenged idea of god

-insufficient evidence

- mechanism of inheritance was. It known until 50+ years later

Inheritance Theories

Alternative theories to natural selection with limitations.

Alfred Russel Wallace theory

independently identified process of evolution by natural selection (1858)

Speciation

Process by which new species arise over time.

Genetics Development

Evolution of genetic understanding, including Mendel's work.

Fossils

Remains of ancient organisms, providing evolutionary evidence.

Fossil Formation from casts

- fossils formed when an organism is buries in a soft material like clay

-clay later hardens leaving a cast

Fossil formation from gradual replacement by minerals

-teeth and bones don't decay easily and are replaced with minerals

-they form a rock like substance

Fossil formation from preservation in places where no decay happens

- in amber and tar pits there's no oxygen or moisture so decay microbes can't survive

- in glaciers it's too cold for the decay microbes to work

- peat bogs are too acidic for decay microbes

Why are there few traces of early life forms

Many early forms of life were soft bodied so decayed away completely

Fossils have been destroyed

Extinction Causes

-environment changes quickly

-new predator

-new disease

Antibiotic Resistance- MRSA

When strains of bacteria are resistant to antibodies and spread

The resistant strain will spread and won't be stopped as people aren't immune so antibodies won't work on them

how to control antibiotic resistance

-don't get prescribed antibiotics inappropriately(treating non serious infections)

-restrict agriculture of antibiotics

-high cost of antibiotics