Developing a Theory to Explain Change Flashcards
Believed all species of organisms has been created independently of one another and had remained unchanged ever since.
- Believed to be true for over 2000 years
Aristotle and Pluto
Statement that makes successful predictions about a broad range of observations.
Theory
What could be evidence for extinction?
Fossil Record
Destructive natural events which were believed to have killed numerous species each time they occured.
Revolutions
Believed that species increased in complexity over time, until they reached perfection.
- Organisms could acquire characteristics and pass onto children (Ex. develop large muscles and therefore offspring will have large muscles).
Lamarck
What understanding refuted Lamarck’s ideas?
The understanding of Genes and Heredity
Believed evolution takes place because more organisms are produced than can survive, and only the best organisms best suited to their environment survive to reproduce and pass on their advantageous traits to their offspring.
Charles Darwin
Evolution occurs in 5 steps. Name them. 🎀
- Overproduction
- Struggle for existence
- Variation
- Survival of the Fittest
- Origin of new species
Why does Overproduction happen in evolution?
The number of offspring produced by a species is more than can actually survive. (Higher chance of survivors)
What does Struggle for Existence mean in evolution?
Every living organism faces a constant struggle to survive.
- Only a fraction of offspring will survive due to fierce competition for food, mates, shelter, etc.
What does Variation mean in evolution?
Individuals of a given species very
- Only identical twins are the same
What does Survival of the Fittest (Natural Selection) mean in evolution?
Nature selects which organisms will survive based on traits that give them an advantage in the environment.
What does Origin of New Species mean in evolution?
The organisms that survive pass on their traits to offspring.
- This eventually can lead to speciation.
What are examples of ‘Evidence of Evolution?
- Fossil Record
- Biogeography
- Anatomy
- Embryology
- Molecular Biology
______ ______ (Evidence of Evolution)
- Fossils found in young layers of rock are much more similar to species alive today.
- Fossils appear in Chronological order. (Not all organisms appear in the fossil record at the same time).
Fossil Record
____________ (Evidence of Evolution)
- Study of the past and present Geographical Distribution of organisms.
- Geographically close environments are more likely to be populated by related species than are locations that are geographically separate but environmentally similar.
- Closely related species are almost never found in exactly the same location or habitat.
Biogeography
_______ (Evidence of Evolution)
Different types of structures
- Homologous structures
- Analogous structures
- Vestigial structures
Anatomy
Structures that have similar structural elements and origin but may have different functions. (Ex. human arm, cat leg, whale flipper, and bat wing.)
Homologous Structure
Structures that have a different structure but perform similar functions, even though the organisms do not have a common evolutionary origin. (Ex. wings in flying animals like bats, birds, and insects).
Analogous Structure
Rudimentary structures that serve no useful function.
- A reasonable explanation is that they once served some function in an ancient ancestor.
Vestigial Structures
__________ (Evidence of Evolution)
- The embryos of different organisms exhibit similar stages of embryonic development.
- Similarities among embryos in related groups point to a common ancestral origin.
- Similarities in the embryos of a lizard, tortoise, pig, and mammals provide evidence of evolution.
Embryology
_________ _______ (Evidence of Evolution)
Evolutionary relationships among species are reflected in their DNA and Proteins.
Molecular Biology
Molecular Biology provides evidence that helps support the idea of common ancestry and evolution through what?
Natural Selection
__________ _________ (Evidence of Evolution)
The process of humans selecting and breeding individuals with desired traits.
- Used to alter appearance, behaviour, and chemical makeup of plants and animals.
Artificial Selection
What type of evidence supports punctuated equilibrium?
Fossil Record
