Evolution, Natural Selection and Adaptations

• Evolution is reproduction with modification in future generations, driven by genetic inheritance.
• It involves heritable changes in populations, influenced by mutations, natural selection, and genetic drift.
• Evolution leads to altered gene frequencies in a population.
• Mutations create genetic variation, and favorable mutations increase survival and reproduction.

Natural Selection

• Natural selection is a key evolutionary mechanism.
• Individuals with favorable traits survive and reproduce more.
• These traits increase an organism’s fitness (ability to survive and reproduce).
• Favorable traits become more common over time.
• Mice that avoid predators are more likely to pass on their genes.

Adaptations and Biomimicry

• Adaptations are traits evolved through natural selection that aid survival.
• Adaptations can be physical, behavioral, or physiological.
• Biomimicry is when humans learn from adaptations to solve problems.
• Gecko climbing inspires new adhesives.

Genetic Engineering

• Genetic engineering directly alters DNA to introduce or modify traits.
• This can significantly change a population’s gene pool.
• Disease-resistant crops can be created by inserting genes from other species.
• This process can accelerate evolutionary changes.

Gene Pool and Genetic Drift

• A gene pool is all genetic material in a population.
• Genetic drift is random changes in allele frequencies, especially in small populations.
• It occurs due to chance events.
• Genetic drift reduces genetic diversity.

Gene Flow

• Gene flow is the movement of alleles between populations through migration or reproduction.
• It introduces or removes genetic material, altering the gene pool.
• Migration can increase genetic diversity.

Design Thinking in Science

• Design thinking is a problem-solving approach involving understanding, solutions, prototyping, testing, and refinement.
• It is an iterative process applicable to scientific methods.
• It emphasizes observation, data collection, and innovative solutions.

Survival of the Fittest

• "Survival of the fittest" means individuals with traits that enhance survival and reproduction are more likely to pass on their genes.
• This improves an organism’s ability to thrive in its environment.
• These traits become more common.

Mechanisms of Evolution

• Evolution is driven by mutations, natural selection, genetic drift, and gene flow.
• Mutations introduce new genetic variations.
• Natural selection favors traits that enhance survival and reproduction.
• Genetic drift and gene flow alter allele frequencies.

Changes in Populations

• Evolution occurs at the population level, not the individual level.
• Genetic changes accumulate over generations, leading to new traits.
• These changes can result in new physical or behavioral traits.

Darwinism theory

• Charles Darwin developed the theory of natural selection.
• Darwin observed unique species on the Galapagos Islands studying the finches and their beaks
• Published in "On the Origin of Species" in 1859
• Darwin explained how species evolve over time through natural selection.

Steps of Natural Selection

• Variation: Genetic variation within a population leads to differences in traits.
• Selection Pressure: Environmental changes make some traits more advantageous for survival.
• Reproduction: Individuals with advantageous traits are more likely to survive and reproduce.

Selection Pressures

• Selection pressures are external factors influencing survival.
• Pressures can be positive or negative.
• Examples: resource availability, temperature, predators, or diseases.

Peppered Moths Example

• Peppered moths demonstrate natural selection.
• Light moths were initially camouflaged.
• Pollution darkened trees during the Industrial Revolution.
• Dark moths became better camouflaged.
• Over time, the population shifted to predominantly dark moths.

Galapagos Finches Experiment

• An experiment simulating the feeding habits of Galapagos finches demonstrates how beak shape affects survival.
• Simulating the effects of available food sources.
• Changes in food affected finches.
• This highlights the role of natural selection.

Adaptive Value

• Adaptive value is the usefulness of a trait in helping an organism survive and reproduce.
• Traits with positive adaptive value increase chances of survival.
• These traits become more common.

Biomimicry Imitating Nature

• "Bio" means life, and "mimicry" means to imitate, imitating nature to solve human problems.
• It’s used in design thinking, applying plant and animal adaptations.
• Velcro was invented by George de Mestral, inspired by burrs sticking to his dog.

Genetic Modification

• Genetic engineering/Modification - various techniques
• Goal/outcome determines technique choice.
• Somatic cell modification affects only the individual, not future generations.
• Germline modification affects reproductive cells and passes changes to offspring.
• Examples of techniques: gene therapy, gene editing (CRISPR), cloning, transgenic modification, and gene silencing.

Fixing Protein Synthesis

• Genetic engineering aims to correct mutations affecting protein production.
• Proteins are essential for cell function; shape determines function.
• DNA mutations can miscode protein production, resulting in non-functional or harmful proteins.
• Fixing genetic mistakes ensures correct protein shapes and proper biological function.

Genetic Engineering Basics

• DNA contains genes that code for proteins.
• Genetic engineering aims to fix errors in genes, ensuring correct proteins.
• Genes from one species can be inserted into another.

Transgenic Modification

• Insulin Production transgenically modified bacteria that can produce insulin.
• Potentially leads to evolutionary changes.
• Long-term effects and on genetic diversity may occur.

Pros of Genetic Engineering

• Harmful genetic mutations can potentially be eliminated from the gene pool.
• Therapeutic applications increasing life expectancy.
• Agriculture benefits in agriculture, such as drought-tolerant crops.
• Conservation or reviving of endangered species.

Cons of Genetic Engineering

• Reduces genetic diversity.
• Somatic cells modifications only passed onto individuals.
• Traits advantageous are subject to change.
• Some modifications may cause harm.

Genetic Engineering and Thinking

• Design Focuses on consumer needs
• Testing: Computer Modeling (bioinformatics), Cell, Animal, Human testing
• Rigorous and lengthy testing is a thorough process.