B14. Evidence for evolution and extinction Flashcards
What is evolution?
Evolution is described as a change in the inherited characteristics of a population over time through a process of natural selection (due to mutations) which may result in the formation of a new species.
Describe fossil evidence for evolution.
Fossil evidence for evolution includes the remains or traces of organisms preserved in rocks, which show changes in species over time and provide insights into the history of life on Earth.
What is a fossil?
Fossils are the ‘remains’ of organisms from millions of years ago, which are found in rocks.
What are the 2 major forms of evidence that evolution has and does occur?
1) Remains of dead organisms have been found (i.e. fossils).
2) Bacteria have become resistant to antibiotics (antibiotic resistance)
What does a new branch on an evolutionary tree diagram show?
A new branch in the tree shows wherespeciationhas occurred (when a new species has evolved).
What are antibiotics?
Antibiotics are chemicals that damage bacteria and eventually kill them. Each types of antibiotic interferes with the bacteria’s life processes, e.g making a cell wall.
They do not kill viruses, protozoa or fungi.
Explain how antibiotic resistance provides evidence for evolution.
Antibiotic resistance occurs when bacteria evolve resistance to antibiotics through natural selection, leading to the survival and reproduction of resistant strains and the emergence of new strains over time.
Describe the process of natural selection in antibiotic resistance.
In antibiotic resistance, bacteria with genetic mutations that give resistance to antibiotics are more likely to survive and reproduce in the presence of antibiotics, leading to the growth of resistant strains in a population.
What is extinction?
Extinction is the permanent disappearance of a species from the Earth, typically due to environmental changes, competition, predation, or catastrophic events.
Discuss the role of mass extinctions in the history of life on Earth.
Mass extinctions are events in which a significant proportion of Earth’s species become extinct in a relatively short period, leading to major changes in biodiversity and the evolution of new species.
How does the fossil record provide evidence for extinction?
The fossil record contains evidence of species that existed in the past but are no longer present, providing insights into the timing, causes, and consequences of extinction events throughout Earth’s history.
Why can fossils be problematic at evidence for evolution?
Fossils form rarely and only in certain conditions.
Parts of early organisms were mostly soft bodied so they couldn’t form fossils.
Therefore there is no trace of some organisms (i.e. there are gaps in the fossils records).
This is why Scientists cannot be certain about how life began on earth.
What is the binomial naming system?
The binomial naming system, developed by Carl Linnaeus, is a way of naming species using two parts: the genus name and the species name. It provides a universal and standardized method for identifying and classifying organisms.
What is the significance of Carl Woese’s work in the field of classification?
Carl Woese proposed the classification of organisms into three domains: Archaea, Bacteria, and Eukarya. His work provided a more accurate representation of evolutionary relationships among organisms.
What is an example of a species name using the binomial naming system?
An example of a species name using the binomial naming system is Homo sapiens, where “Homo” is the genus name and “sapiens” is the species name. This name refers to modern humans.
