What scientific evidence exists to support Darwin's theory that present-day organisms have evolved from organisms in the past AND how does it support the theory?
Theory of evolution
Fossil Records
Anatomy
Biogeography
all living things have Common ancestors
Charles Darwin and Alfred Russel Wallace
Molecular Biology
Direct Observations
Able to reconstruct animals or plants
Soft part decay, hard fossilise
older organisms (simple)
Younger organisms (complex)
Shows common structures within the body
Further back in time
hard to distinguish Whale to Land mammal
nostrils moved further back on the skull
Jean-Baptist Lamarck
Traits with offsprings
Could not prove theory
Change in bone size and structure to better suited environments
Any change in heritable traits within a population across generations
mid 1800s
Natural selection
The process by which only the more favourable traits survive in specific environments
Macroevolution
Microevolution
major evolutionary change over a long period of time
small changes within a species over a short period of time
Variability
heritability
over-reproduction
Competition
No breeder necessary
Produce order and complexity
Observable changes that happen within a short period of time
e.g.
DDT resistant insects
Modifications to help the survive
Weeds turning into different vegetables by farmers
Galapagos Islands
e.g.
Finch population
Change in beak size and thickness
Isolation causes variations within the populations
looks at the distribution of plants and animals
Different landscapes force animals to adapt
can line with different continents
Similar to species close by
Similar to species that lived together before split
Animals are not suited to live outside their environment
Similarities and differences in macromolecules
similarities and differences in the structure of different organisms
Cetaceans
evolved from land mammals
Like features
Unique bone structure and body plan
Common ancestral traits
Embryology
development stages of different species
e.g.
nostril grooves on dolphins faces during early stages
Shows common ancestral traits
shows common development
total number of fossils found providing information about past life on earth
Homologous
reduced size in vestigial structures
underdevelopment of body parts
Mutations
spontaneous change in the DNA sequence of an offspring
Gene pools
varieties within a population
Genotypes
Favoured genes survive and reproduce
Unfavored genes die out
caused by random errors in replication or repair of DNA
each islands has its own genotype
DNA
Contain chemical codes
Holds ancestral information
"Biology In Focus: Year 11"
"Biology In Focus: Year 11"
"Biology In Focus: Year 11"
"Science Essentials For NSW: stage 5"
"Science Essentials For NSW: Stage 5"
Whales have hair, no gills, arms, legs and similar bone structure to mammals
"What is the Evidence for Evolution?" Stated Clearly