Biol 301 1nd EditionExam # 1 Study Guide Lectures: 1 - 5Lecture 1- Ecology – study of interactions of organisms with one another and with their environment. Also the study of the distribution and abundance of organisms- Evolution – change in a population’s gene pool over time. Science of the origins of biological diversity and its distribution- All ecological processes occur in the context of evolutionary history. All evolutionary processes occur in an ecological context- Ecological systems – biological entities that have their own internal processes and interact with their external surroundingsa. Individual – the most fundamental unit of ecology. Individuals acquire nutrients ane energy, and produce waste. Individuals have a membrane boundary that separates internal processes from the external environmentb. Species – individuals that are capable of interbreeding or share genetic similarity.This definition isn’t universal and there are many definitions of speciesc. Population – individuals of the same species living in a particular area and interbreeding. Boundaries can be natural like forest edges, or political like state linesi. Geographic range (distribution) is the extent of land or water within which a population livesii. Abundance is the total number of individualsiii. Density is the number of individuals per unit areaiv. Composition is the makeup in terms of age, gender or geneticsd. Community – populations of species living together in a particular area. Boundaries are not always rigid, and may cover small or large areas. Includesmany types of interactions such as predation and competition. Ex: cheetahs and gazelles on the African plainse. Ecosystem – one or more communities of living organisms interacting with their nonliving physical and chemical environment. Research is focused on movement of energy and matter between physical and biological component. Theis includes the flow of material from pools of elements, such as carbon, oxygen, hydrogen, nitrogen, and phosphorus. Boundaries are often not distinct. Abiotic environments: nitrogen cyclef. Biosphere – all ecosystems on Earth. Distant ecosystems are linked together by exchanges of wind and water and by the movement of organisms- Population approach – examines variation in the number, density, and composition of individuals over time and space.- The first law of thermodynamics (conservation of matter) states that matter and energy cannot be created or destroyed, but can change form.- Ecological systems gain and lose matter and energy. A dynamic steady state occurs whengains and losses are in balance- Natural selection is a change in the frequency of genes in a population through differential survival and reproduction of individuals that possess certain phenotypesg. 3 Requirements of Darwin:h. Individuals vary in their traitsi. Traits are heritablej. Variation in traits causes some individuals to experience higher fitness (survival and reproduction). Better fitness can pass on better genes to offspring- First organisms were prokaryotes (single celled bacteria) and archaea without distinct organelles. Prokaryotes can utilize sources of energy that most other organisms cannot, such as N2 and H2S gas. Cyanobacteria can photosynthesize- At some point, one bacterium engulfed another bacterium. The engulfed bacterium became mitochondria, and this ancestor gave rise to all eukaryotes, or organisms with distinct cell organelles.- Mitochondria evolved into photosynthetic chloroplasts. These organisms increased the abundance of oxygen in the atmosphere, allowing other plants and animals to survive.- Hypothesis – ideas that potentially explain a repeated observation. A particular hypothesis can rarely be confirmed beyond a doubt. Hypothesis generate predictions – ifobservations confirm the prediction, the hypothesis is strengthened (not proven). If observations fail to confirm the prediction, the hypothesis is weakened. Hypotheses are not predictions. It is a proposed explanation for how the world works.- We often wish to understand two components of such a phenomenon:1. How? (Proximate cause) what drives it2. Why? (Ultimate causes) evolutionary- Proximate hypotheses – address the cause of immediate changes in individual phenotypes or interactions. The specific and immediate cause. Ultimate hypotheses – address the fitness costs and benefits of a response. Looking at the evolutionary impact, long term. Predictions – statements that arise logically from hypotheses. Hypotheses aren’t a prediction. Manipulative experiments – where a hypothesis is tested by altering a factor hypothesized to be the cause of a phenomenon. Treatment – the factor that we want to manipulate in a study. Control – a treatment that includes all aspects of an experiment except the factor of interest. Experimental unit – the object to which we apply a manipulation. May be natural (lakes) or artificial (microcosms), and may vary in size by several orders of magnitude. Replication – being able to produce a similar outcome multiple times (the number of experimental units per treatment). Randomization – a requirement for manipulation experiments; every experimental unit must have an equal chance of being assigned to a particular treatment.- Natural experiments – an approach to hypothesis testing that relies on natural variation in the environment to test a hypothesis. Mathematical models – representations of a system with a set of equations that correspond to hypothesized relationships among the systems components. Ecologists often test mathematic models using natural or manipulative experiments.- Environments dominated by humans (cities, farms, exc.) are also ecological system. Humans depend on the proper functioning of these systems. Humans consume massive amounts of evergy and resources and produce large amounts of waste- Greenhouse gases – compounds in the atmosphere that absorb infrared heat energy emitted by earth and then emit some of the energy back toward earth. High amounts of these gases can increase average Earth temperatures.- Nemoria Story- A ‘bivoltine’ life cycle. From inchworm > caterpillar > summer form > inchworm > caterpillar > early spring form- In spring, Oaks produce catkins (flowers) and Nemoria caterpillars look like catkins- In summer, there are no catkins, and Nemoria caterpillars look like twigs- How do they know which to mimic?