Case 13: A fictious scientific debate BBS1001 2023/2024
17 oktober 2023
Keywords
- Genotype and phenotype
- Development of different species
- Inheritance
- Evolution
- Acquired characteristics
- Evolution theories
- Darwin
- Gain or loss of functionality by the environment
- Lamarck
- Epigenetic
- Gene transfer
Problem statement
Genetic evolution
Learning goals
1. What is evolution?
2. Darwin’s and Lamarck’s evolution theories
3. Difference between those theories (conception of species, mechanism of new
species production, example)
4. What is epigenetics in Lamarckism? (DNA methylation, histone modification,
chromatin structure, RNA modification)
5. What is speciation?
, Case 13: A fictious scientific debate
1. What is evolution?
Evolution I the process by which different kinds of living organism are believed to have
developed from earlier forms during the history of the earth. Species change in the
characteristics over several generations and relies on the process of natural selection.
- The theory of evolution is based on the idea that all species are related and gradually
change over time.
- Evolution relies on there being genetic variation in a population which affects the
physical characteristics (phenotype) of an organism.
- Some of these characteristics may give the individual an advantage over other
individuals which they can then pass on to their offspring.
Natural selection (survival of the fittest)
- Charles Darwin’s theory of evolution states that evolution happens by natural
selection.
- Individual in a species show variation in their phenotype. This variation is because of
differences in their genes.
- Individuals with characteristics best suited to their environment are more likely to
survive in finding food, avoiding predators, and resisting diseases. These people are
more likely to pass their genes on to their offspring.
- As a consequence, those individuals most suited to their environment survive and
given enough time, the species will gradually evolve.
Different types of evolution:
Convergent evolution
When the same adaptions evolve independently, under similar selection pressures. For
example, flying insects, birds and bats have all evolved the ability to fly, but independently
of each other.
Co-evolution
When two species or groups of species have evolved alongside each other where one
adapts to changes in the other. For example, flowering plants and pollinating insects such as
bees.
Adaptive radiation
When a species splits into a number of new form when a change in the environment makes
new resources available or creates new environmental challenges or new natural barriers.
For example, finches on the Galapagos have developed different shaped beaks to take
advantage of the different kinds of food available on different islands.
Divergent evolution
Parallel evolution
2. Darwin’s and Lamarck’s evolution theories
Darwin’s theory
Natural selection:
1. Overproduction: individuals produce more offspring than necessary for the survival
of the species.
17 oktober 2023
Keywords
- Genotype and phenotype
- Development of different species
- Inheritance
- Evolution
- Acquired characteristics
- Evolution theories
- Darwin
- Gain or loss of functionality by the environment
- Lamarck
- Epigenetic
- Gene transfer
Problem statement
Genetic evolution
Learning goals
1. What is evolution?
2. Darwin’s and Lamarck’s evolution theories
3. Difference between those theories (conception of species, mechanism of new
species production, example)
4. What is epigenetics in Lamarckism? (DNA methylation, histone modification,
chromatin structure, RNA modification)
5. What is speciation?
, Case 13: A fictious scientific debate
1. What is evolution?
Evolution I the process by which different kinds of living organism are believed to have
developed from earlier forms during the history of the earth. Species change in the
characteristics over several generations and relies on the process of natural selection.
- The theory of evolution is based on the idea that all species are related and gradually
change over time.
- Evolution relies on there being genetic variation in a population which affects the
physical characteristics (phenotype) of an organism.
- Some of these characteristics may give the individual an advantage over other
individuals which they can then pass on to their offspring.
Natural selection (survival of the fittest)
- Charles Darwin’s theory of evolution states that evolution happens by natural
selection.
- Individual in a species show variation in their phenotype. This variation is because of
differences in their genes.
- Individuals with characteristics best suited to their environment are more likely to
survive in finding food, avoiding predators, and resisting diseases. These people are
more likely to pass their genes on to their offspring.
- As a consequence, those individuals most suited to their environment survive and
given enough time, the species will gradually evolve.
Different types of evolution:
Convergent evolution
When the same adaptions evolve independently, under similar selection pressures. For
example, flying insects, birds and bats have all evolved the ability to fly, but independently
of each other.
Co-evolution
When two species or groups of species have evolved alongside each other where one
adapts to changes in the other. For example, flowering plants and pollinating insects such as
bees.
Adaptive radiation
When a species splits into a number of new form when a change in the environment makes
new resources available or creates new environmental challenges or new natural barriers.
For example, finches on the Galapagos have developed different shaped beaks to take
advantage of the different kinds of food available on different islands.
Divergent evolution
Parallel evolution
2. Darwin’s and Lamarck’s evolution theories
Darwin’s theory
Natural selection:
1. Overproduction: individuals produce more offspring than necessary for the survival
of the species.
