Intro to Ecology and Evolution

what is ecology

• a subdiscipline of biology that studies how organisms interact with each other and with their environments

• understanding how biotic and abiotic factors influence the abundance and distribution of organisms

what are the scales of ecology

• biosphere

• ecosystem

• community

• population

• organism

what are ecosystems

all living things in a particular area, along with all the non-living components of the environment with which life interacts

what is a community

the array of living organisms occupying an ecosystem

what is a population

all individuals of a species living within the bounds of a specified area that interbreed with each other

what is an organism

individual living things (each plant or animal in the pop)

who was the founder of evolution

Theodosius Dobzhansky in 1964

what is evolution

• the process of biological change through which species accumulate differences from their ancestors as they adapt to different environments

• helps explain both the diversity and unity among organisms

how are ecology and evolution linked together

• evolution is the process by which species/pop adapt to their enivorment

• ecological circumstances may change over short or long periods of time

why are these topics important

• concepts in ecology and evolution can help us understand modern problems

• disease ecology and evolution (where disease are found and how strains or vectors can evolve resistance to treatments)

• conservation biology (what are the specific needs of endangered species and how can we prevent species/pops from going extinct)

evolutionary conservation

• the more functionally diverse a system is, the more it is likely to be productive

• by selecting plant species that are more distantly related, there is more chance that they will have evolved functional differences

• leads to overall increase in plant biomass

what is the main difference between an ecosystem and a community

an ecosystem includes both living organisms and nonliving factors in a particular area, while a community consists only of the living organisms within that ecosystem.

the latitudinal diversity gradient is an example of a cline which affects the distribution of species of animals and plants. describe other such clines that are present in nature?

why can evolution be in both the diversity and the unity across living organisms

Evolution explains unity among organisms due to how all living things share a common ancestor, which explains the diversity because of different populations adapt over time to thrive within the different enivornments.

A typical prokaryotic cell has about 3,000 genes in its DNA, while a human cell has about 21,300 genes. About 1,000 of these genes are common to both types of cells. Explain how such different organisms could have this same subset of 1,000 genes. What kind of functions might these shared genes have?

The prokaryotic and human cells come from a common ancestor. The genes have adapted to perform cellular functions that are needed for survival. By adapting to different environments the cells more complex, which leads to differences in the amount of genes.

the upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. however, genetic data suggests that all three species diverged from a common ancestor at about the same time. can you give an explanation as to why the whale forelimbs anatomy is so different.

describe a scenario showing how ecological change and evolution can affect another

pollution has run off from factories and fish die because to cannot tolerate the toxins. some of the fish had developed genetic traits that made them more resistant to pollution, which made them to survive. the fish that survive gets their population to grow, allowing that genetic trait to be passed on.