DESCENT WITH MODIFICATION

• Descent with modification - refers to the passing on of traits from parent organisms to their offspring.
• The passing on of traits is known as heredity
• the basic unit of heredity is the gene
• Gene - Are the blueprints for making an organism and as such hold information about its every conceivable aspect.
• Descent with modification - refers to the species that change over time giving rise to the new species and share a common ancestor
• Descent - may occur through simple clonal reproduction or complex sexual reproduction.
• Lineage - results from descent through time
• Modification - refers to a change in genetic material that is transferred from parents to offspring.
• Charles Darwin - he was born in western england
• Clergyman - someone who is a melee priest bishop leader
• Galapagos island - had a great impact on his thinking about evolution
• According to charles darwin all species descended from only a few life forms that had been modified over time
• Geographic isolation - potential mates occupy different areas or habitats does they never common contact reverse change course mountains price continents drift organisms migrate and what was once a continuous population is divided into or more smaller populations
• Temporal isolation - different groups may not be reproductively mature at the same season or month or year example are individuals that have bold behavioral types might be more likely to feed or to make during times of high predation risk than individuals with shy temperament types that are less likely to be active during risky periods
• Behavioral isolation - patterns of courtship are different example are some words that construct elaborate bowers and locate them with different colors in order to who females if two insufficient species evolve in differences in this mating ritual it might permanently isolate them and complete the process of specification
• Mechanical isolation - differences in the productive organs prevent successful interbreeding lack of it between sexual organs this is a big issue for insects with variable shape gentalya this the cell fly penises illustrate just how complex insect genitalia may be
• Gamete viability isolation - acts as a barrier to gene flow between species contributing to reproductive isolation and the maintenance of species boundaries it is one of the mechanisms that can lead to speciation by preventing the formation of viable hybrid offspring between different species