Week Two Lecture Notes
Week Two Lecture Notes BIO 227
Popular in Wildlife Conservation Biology
Popular in Department
This 6 page Class Notes was uploaded by Miri Taple on Tuesday February 23, 2016. The Class Notes belongs to BIO 227 at California Polytechnic State University San Luis Obispo taught by Dr. Lisa Needles in Fall 2015. Since its upload, it has received 13 views.
Reviews for Week Two Lecture Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 02/23/16
9/30/15 Review: Where is density? (SAIL) – structural complexity, area, isolation, latitude Latitude Rapoport’s “Rule”: As latitude decreases, the geographic ranges of individual species shrink steadily. • Species at higher latitudes tend to extend across greater geographic area. Species near the tropics tend to be more highly localized • Richness works in an opposing way to range 500 Richness Range 0 0 Latitude 70 • Topical biodiversity is highly diverse and also highly localized • Tropical areas have high alpha, beta, and gamma diversity Area Species richness can increase with area • More habitat • More resources that are spread out • Genetic variation increases, so allows for stability and longevity of species • Larger area able to sustain a larger population • Area sensitive species • Low density species in large areas Double area… 10 % increase in the number of species 10 x increase in area… 2 x increase in the number of species Structural Complexity Allows for different habitats • Marine kelp forest • Coral reefs • Tropical rain forest Isolation Isolation reduces richness (# species) but increases endemism (# unique species) • Islands have fewer species but a higher proportion are found nowhere else • A large island close to shore will have more species than a small island close to shore (area and proximity to mainland correlate to the increase in the number of species) 25 global “Hot Spots” of richness, endemism, and threat • Madagascar: Biodiversity hot spot, endemism especially despite it being an island o Ex. The baobab tree is unique to the island o 4 largest island, great climatic and geographic diversity (topical rainforests, grasslands, etc.) o 12,000-15,000 different plant species o isolated for more than 70 million years, through evolution, unique species have developed. o Most species there are endemic Biodiversity in the U.S.A • U.S. state with highest species richness = California (hot spot of richness and endemism) o California floristic province- 4,425 vascular plant species (48% endemic) o Yellow-billed magpie (endemic to CA) o It is a hot spot due to diverse topography, bioregions, and geology (serpentine soil = low Ca to Mg ratio and Vernal Pools = wetland that dries up for part of the year) • Hawaii- island that has a high amount of endemism as well Introduction to Populations Population: multiple individuals of the same species in the same general geographic location • the hierarchy of biotic organization = biosphere (top) atoms (bottom) every level of organization contains all the lower levels but also has its own properties 1. organism- unit of natural selection (survival and reproduction) 2. population- unit of evolution 3. community- interactions among populations 4. ecosystem- energy flux and cycling of nutrients 5. biosphere- global processes • Populations have 4 emergent properties 1. Quantity 2. Composition (genetic variation, male/female, etc.) 3. Special extent (geographic distribution of population) 4. Dynamics (change over time, traits vary with time) • Zones of physiological tolerance: all organisms have optimal environmental conditions, departure from these conditions (higher or lower) causes reduction in fitness High fitness… low stress (disease, drought, competition, climate change, etc.) Low fitness… high stress o With environmental stress most species will stop reproducing, however in some cases they will reproduce more than usual to try and compensate for the loss of something else. o Migration- round trip movement, usually seasonal, to escape harsh environmental conditions (often related to temperature or availability of food) § Bird “flyaways” in North America § Pacific, central, Mississippi, etc. flyaways § Arctic terns have longest migration route: pole to pole o Dormancy (hibernation, etc.)- temporary reduction in activity and metabolic rate to survive harsh environmental conditions. Population dynamics Population levels are controlled by: • Birth rate • Death rate • Immigration • Emigration A meta population: Species A population A… species A population B… species A population C Some overlap in-between the populations over say a river or something of the sort. • Population growth is exponential but cannot sustain that way for very long and turns logarithmic (J-curve v. S-curve) Factors that contribute to potential for reproduction • Fecundity: # of offspring per reproductive bout (humans generally 1, mice 6-10) • # Reproductive bouts: in general, the more reproductive bouts the more offspring • maturity time or age of first reproduction o gorillas, whales, elephants: 10-15 yrs. o Fox or goose: 9 months/ 1 year o Lemmings or field mice: 2-3 weeks Slow v. fast continuum in life history traits • K-selected (elephant, people) o Long lifespan o Late age of first reproduction o Few offspring with large investment in each o Low juvenile mortality • R-selected (mussels, rats) o Short lifespan o Early age of first reproduction o Many offspring with little investment in each o High juvenile mortality o Carrying capacity (k): the general capacity of habitat to support wildlife, realized population growth rate is proportional to the environment’s carrying capacity Allee effect: when small populations have lower fitness populations that fall below a certain “critical minimum” may have diminished survival and reproduction a) Individuals may be unable to and and acquire POLYLEARN • Penguins: environmental protection by huddling • Musk oxen: defensive phalanx • Allee effects can have a “snowball effect” (positive feedback loop) • “extinction vortex” small population = reduced fitness = smaller population • external factors (evil quartet) 1. habitat destruction 2. exotic species/ diseases 3. overexploitation 4. ecological linkages/ cascading effects 9/28/2015 The Dawn of Conservation (1890-1900) • Passage of the Lacey Act of 1900 to control market hunting o “the game and wild birds’ preservation and disposition act” o until passage only states had addressed wildlife policies o new topics- non game wildlife products, interstate commerce, and exotic species o Problem: before, states didn’t have the jurisdiction to enforce wildlife policies if it was transported out of state o Solution: now it is a federal offense to transport illegally killed game across state lines • Presidency of Theodore Roosevelt o “The rough rider” o pelican island, FL (first national wildlife refuge 1903) established by Roosevelt to protect breeding habitat o increase in federal land holdings o Yosemite- federally protected, integrated as a national park o “Teddy’s Bear” and the sportsman’s ethic of fair chase, defender of wildlife o avid conservationist and avid hunter • This period represents the origins of federal government role in wildlife management o The rise of professional wildlife management (1930-1940) § Scientific foundations § Figurehead: Aldo Leopold, U.S. Forest Service § “Game management” textbook, he was a philosopher and writer… “Sand County Almanac” • Wildlife management infrastructure and funding o 1934: Duck Stamp Act- allowed for habitat for ducks, had to carry duck stamp to legally hunt them, the money went to preserving land for the ducks o 1937: Pittman-Robertson Act- created federal sales tax on guns, ammunition, and hunting equipment, to be directed toward wildlife restoration o 1935: Soil Conservation Service (Natural Resources Conservation Service) o 1936: National Wildlife Federation Environmental Movement (1960-1980) • Figurehead: Rachel Carson… “silent spring” about DDT- an effective killer and softened the eggs of birds. • 1964: Wilderness Act • 1964: Wild and Scenic Rivers Act • 1966, 1969: Precursors to endangered species act • 1973: Endangered Species Act- species put on a list where regulations were then enacted, protection for non-game species and their habitat • 1976: Marine Mammal Protection Act • 1975: Convention on International Trade in Endangered Species (CITES) Establishment of Modern Framework • NEPA, EPA, Clean Air Act, Federal Pesticides Control Act, Safe Drinking Water Act, Toxic Substances Control Act, Clean Water Act, Superfund (CERCLA) Quantifying Biodiversity • The “currency problem” o Biodiversity can mean either species richness or the combination of species richness and evenness (how many species and how evenly divided… # of species v. abundance) • Caveats to richness: not all species have the same “conservation value” o Native, endemic, localized, rare, threatened/declining, taxonomic (nothing close to it exists), uniqueness, key ecological role, value to humans… higher conservation priority • The special scales of biological diversity (alpha, beta, gamma diversity) Ex. 4 sites, each containing 5 species 5 spp. 5 spp. 5 spp. 5 spp. Ex. 4 sites, each containing 5 species (alpha diversity) How many species across the whole area (all for sites together) … answer depends on how much overlap exists among the 4 sites (whether turnover is high or low) 5 abcd 5 fghij high v. 5 abcde 5 abcde low • Beta diversity is “turnover” in the species, composition as you go from one site to the next- opposite of overlap Alpha- how many in a site Beta- how does species composition vary across multiple areas (turnover) Gamma- cumulative total biodiversity across multiple areas within a region? #spp in state, country, continent, etc. Gamma diversity is a function of alpha and beta diversity Lowest when alpha and beta are low Highest when alpha and beta are high Intermediate when either alpha or beta are low etc. Global Biodiversity • How many species exist worldwide? How to define species? Documented? • Biological species concept (BSC): Species are groups of actually or potentially interbreeding populations, which are reproductively isolated from such other groups – Mayr 1942 o Subspecies are recognized o Shortcomings: not applicable to asexual species (bacteria, etc.), not work for “chronospecies” fossil record, hard to use with taxa that hybridize easily (like many plants) o Some species look similar and don’t successfully interbreed o Others look different but can interbreed o 1.9 million described species almost ½ insects o species richness is inversely proportional to body size or mass o patterns from the # of known species to date: § to date about 1.9 million species have been described by science § many of the world’s species remain to be discovered § there are many more species of small things than of big things o vertebrate diversity 63,000 species- half of modern vertebrate species are “fish” the other half are tetrapods (4 limbs) o Ray-finned fishes (30,500) o Birds (10,000) • where is biodiversity? What areas have a lot of species? o 4 fundamental patterns: § latitude-richness increases as latitude decreases (toward tropics) § area- larger areas have more species § structural complexity- species richness increases
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'