BIOL1070MIDTERM IILECTURE REVIEW.Qualified Virginia State University, Exams of Nursing

Download BIOL1070MIDTERM IILECTURE REVIEW.Qualified Virginia State University and more Exams Nursing in PDF only on Docsity! BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Lecture 8 Biodiversity: Evolution and ecology BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University What Determines Global Biodiversity? Global biodiversity is the net outcome of two opposing processes: • Speciation: Increase in diversity • Extinction: Decrease in diversity. •One cannot explain the diversity of life without understanding these two components of evolutionary history. BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University • Biosphere: Regions of the Earth’s crust, waters, and atmosphere inhabited by living things • Ecosystem: A community plus the physical environment • Community: Interacting populations • Population: Organisms of the same species • Organism: An individual; complex individual composed of organ systems • Organ system: Composed of several organs working together • Organ: Composed of tissues functioning to achieve a specific task • Tissue: A group of cells with a common structure and function BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University • Cell: Composed of many molecules; structural and functional unit of all living things Molecule: Unions of two or more atoms • Atom: Smallest unit of an element composed of electrons, protons, and neutrons How could we test these hypotheses? BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University 4. Dispersal / non-native / introduced / invasive: It arrived from somewhere else not nearby (e.g., Seeds transported by migratory birds? Introduced by humans?) 5. Vicariance: It evolved elsewhere, but then the physical landscape itself changed (e.g. continental drift). BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University What happens to the ecosystem when a species is extirpated? Change in the balance Antarctic Food web BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Homework: Based upon this simplified food web, what coul d happen if 25 years after the collapse of the cod population we released millions of adult, juveni le, or larval cod into the Atlantic? BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University C) Starfish will experience a population explosion and drive clams to extinction. D) The market price of crab will increase E) Juvenile cod will have to start feeding on phytoplankton BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Lecture 9 Forest Biodiversity BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Learning outcomes 1. Introduce the woodlots for the Inquiry Case. 2.Derive useful measures of biodiversity. 3.Explore the various aspects of species richness curves. 4.Compare four diversity indices and understand their benefits and short comings. 5.Apply diversity indicies to a management problem. Questions: • What are these and how are they calculated? • Are they correlated with each other or can they vary independently? BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Within a habitat: Alpha Species Diversity α-species diversity: number of species within a habitat Habitat 1 Arboretum Plants BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University How do we know that the Alpha Species Diversity value is accurate? The number of species per specified collection/sample area OR specified number of individuals. Habitat 2 Arboretum Plants BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Clicker Question (Sample Exam Question) Look carefully at these species area curves. Which of the following statements is true about the diversity in the five habitats (AY,OG,KR,KU,SN)? A) Diversity is highest in AY. B) Richness is lowest in SN. C) KR is likely to be over sampled. D) Sampling intensity is almost BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University saturated at OG. E) Sampling intensity is saturated at AY. BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Within a habitat: Evenness • Relative abundance of species in an area. • Often described using the “Shannon Diversity Index”. BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University In other words, SDI is a way of H’ = - i = 1 BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University n i x ln(n i ) BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University calculating how abundant each species is relative to the abundance of the other species in a given habitat. SDI = - [(nspecies 1 / nall species) x ln (nspecies 1 / nall species) + (nspecies 2 / nall species) x ln (nspecies 2 / nall species) + … (nspecies R / nall species) x ln (nspecies R / nall species)] α = alpha diversity (i.e., total number of species). BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University • γ-diversity: Total number of species across all habitats. • Within Habitat 1, α-diversity = 3 species. • Within Habitat 2, α-diversity = 3 species. • Across both habitats, γ-diversity = 5 species. BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University HOMEWORK 1) Calculate α species diversity and species evenness (Shannon’s diversity index) for the trees/shrubs in The Dairy Bush, Brown’s Woods, and the North Campus Ravine (using diagrams provided). 2) Double the number of species in each woodlot and recalculate all indices. What do you notice??? 3) Double the number of individuals in each woodlot and recalculate all indices. What do you notice??? 4) Calculate β and γ species diversity for each combination of two woodlots. You will have to repeat steps 3 and 4 with different values to really appreciate how these indicies work BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Learning outcomes 1) Apply diversity metrics to our three woodlots and consider how these might influence our decision. 2) Understand some of the factors that determine why species are found where they are (and why they are not found where they aren’t). 3) Consider the importance of scale in terms of understanding species distributions. BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University HOMEWORK Calculate α diversity (species richness) and evenness (Shannon’s diversity index) for the trees in each woodlot. Calculate β and γ diversity for each combination of two woodlots. Manipulate the number of individuals and number of species and recalculate. BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University A) Dairy Bush B) Brown’s Woods C) North Campus Ravine BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University What determines species composition? Local scale: Why don’t all three campus woodlots have the same species in them? Regional scale: Why are there different types of trees in southern versus northern Ontario? Global scale: Why doesn’t Ontario have the same species as Costa Rica? Biomes are Ecosystems at a Global scale BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Biome: ◦ Ecosystem level (NOT Community) ◦ Spatial scale = global ◦ E.g. boreal forest Draw these axes and place the corresponding biome letter where you think it should go BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University What determines species composition? What factors place limits on the geographic boundaries of these BIOMES? Terrestrial Biomes are classified on two abiotic gradients Low Plot each on a graph A) Tropical Always look at the axes. In this case cold is at the top of Y, warm at the bottom. Te m pe ra tu re BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Precipitation BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University High BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Terrestrial Biomes are classified on two abiotic gradients A) Tropical B) Boreal / Tundra C) Savanna D) Desert E) Temperate Biomes can be classified on two climatic gradients: Temperature and Precipitation BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Important questions: Are these trends real? Do they apply to all types of organisms? And why might they NOT apply? What might cause such patterns? BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University What is the driver here? Is this true? Is Scale important here? (yes: what about deserts????) Why would population size increase when species diversity decreases? (history of Antarctic diversity…. Once very high with more temperate conditions, moved towards pole and became nasty to live. Most species disappeared, some adapted, those that did adapt experienced low niche competition and thrived in often ridiculous numbers: crabeater seals could range in the area of 50 million individuals) Experiments (field transplant, controlled environment). BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Research Question How would you determine which abiotic factor is limiting the distribution of a species? Field observation of actual range of distribution. Determine ecological tolerances. Correlation between environmental gradients and a species optimum range. BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Tree range limits and temperature Monthly winter temperature < -18oC. Monthly summer temperature >24oC. Sugar maple BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Transplant Experiments: correlation vs causation BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Why is there a tree line? What limits northern tree distributions? BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Which factors limit the tree line? Treatments: A.Underneath herbaceous canopy (shaded, competition for water) B.On bare soil (lots of light, no competition) C.On bare soil, surrounded by herbaceous canopy BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University (lots of light, competition for water) BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Shade (cool), competition for water Full sun (hot), no competition for water Full sun (hot), competition for water BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Carrying Capacity BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Questions • What kinds of factors limit carrying capacity? • How can carrying capacity change over time? • What does the point in the middle represent? BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Population control – Density-dependence BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Population control – Density-independence • Density-dependent factors affect per capita birth or death rates in a way that depends on population density (i.e., the effect is stronger/weaker depending on whether the population is dense/sparse). Examples of density dependence: Would a zombie apocalypse represent a density-dependent or density-independent human population control? BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University •Density-independent factors: factors affect per capita birth or death rates in a way that does NOT depend on population density •Density independent factors can intensify the effects of density-dependent factors – e.g., a hard freeze diminishes the supply of food or prey BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Lecture 12 Population Density and Carrying Capacity BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Homework clicker question Which of the following statements is NOT consistent with the graph A) Treatment B is not transmitted by coughing B) Treatment A’s effectiveness will be really low in rural parts of the country C) Treatment A is the best option to eradicate the population D) You should stop trying Treatment C because it ain’t workin’ E) Treatment A represents a deadly fungus that is spread when two individuals touch BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Learning outcomes 1.Understand factors that affect the abundance of populations. 2.Understand how members of a species may be distributed within a habitat, and the factors that affect these patterns. 3.Understand how abiotic and biotic factors can influence the distribution of species. Treatment B Eff ec tiv en es s o f th e tre at m en t BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Population-level variables Distribution (area or volume) Abundance (N, #) Density (N/area) Birth & Death rates (Δ N/time) Sex & Age Structure (males vs. females) Fecundity (# eggs produced per female) Fertility (% of eggs that produce viable offspring) Production (# offspring produced by a population) Recruitment (# individuals reaching breeding age, includes offspring + immigration) Different organisms have different densities Population Size (N): # of individuals Population Density: #/area or #/volume Mice .025/m2 Ladybird Beetles (ladybugs) 50/m2 Diatoms 5,000,000/m2 BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Population-level variables BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Abundance (N): Density (N/area): Ladybird Beetles (ladybugs) 50/m2 Diatoms 5,000,000/m3 BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University (I – E) BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Spatial Patterns of Distribution CLUMPED EVEN RANDOM (?) BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Humans may exhibit all three patterns • Clumped: Young individuals remain close to their birthplace. When resources are only available in patches or ‘islands’. (This butterfly is confined to habitat patches that contain the plants its larvae feed on.) • Even: Plants: competition for light, water & nutrients. Animals: defense of space (territory). (Northern gannets incubation space determined by “pecking”.) • Random: The result of many factors interacting to influence where individuals settle and survive. (This cactus grew in the shade of a “nurse plant” – the Verde bush.) BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Clicker question Which of the following statements about these hogweed population data is INCORRECT? A. Point B may represent a population that has recently invaded a new area with suitable habitat. B. Point B may represent a population that has recently been treated with effective herbicides but which could recover quickly. C. Point D may represent a population that is experiencing relatively high limitations of resources. D. Point D may represent a population that continues to grow at a very high rate because it is easily outcompeting local plants. x1 00 0 BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University E. Between point B and C the hogweed population experiences exponential growth with relatively few limitations. BIOL1070MIDTERM II L E C T U R E REVIEW.Qualified Virginia State University Learning Outcomes 1. Understand factors that determine potential and actual distributions of species. 2. Understand the effects of biotic factors such as competition for resources on species distributions and trait evolution.