Five Kingdoms of Life (Earth s Biodiversity)

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1 Five Kingdoms of Life (Earth s Biodiversity) Bacteria Protists Fungus Plants Animals prokaryotic eukaryotic eukaryotic eukaryotic eukaryotic single cell consumer (decomposer) or autotroph producer most important decomposer Some bad Streptococcus & Salmonella single cell (A few multi-) consumer or autotroph producer ciliates, ameoba algae, protozoans (malaria), dinoflagellates (Pfiesteria) multi-cell (yeast single) consumer (decomposer) mushrooms, mold, yeast are decomposers some molds, mildews kill plants Evolution = genetic change in population over time. The Big Picture Medium-sized giraffe has mostly medium babies, but there is genetic variability Good mutation causes one to be much taller medium babies Darwin s Theory of Natural Selection If environment changes (taller trees more common), then the tall giraffe will be selected by nature to live & have babies multi-cell autotroph producer mosses, ferns, bushes, shrubs, trees we grow too many annuals & not enough perennials multi-cell consumer (herbi, carni, omni, detritus eaters) Invertebrate (insects #1) Vertebrates (people, etc.) Eventually, all the giraffes that survive will be tall if isolated from short ones or the environment remains favorable for tall giraffes. The species has EVOLVED (changed). Drives evolution & means nature selects who lives, who dies (based on their adaptations) nature selects the smartest, fastest, and best camouflaged to live. (these good things that help animal to survive are called Adaptations)

2 whichever animals have the best adaptations will live and have babies (most babies will inherit good adaptations) 4 observations of natural selection 1. Overproduction- organisms have more offspring than will survive to maturity to ensure some can pass on genes 2. Variation- individuals in a population exhibit inherited variation 3. Limiting Factors limit population- it s a struggle to survive (competition) 4. Differential Reproductive Success- best adapted breed the most & pass on traits & new potential variation Natural Selection can choose certain genes to be successful over others in 3 ways 1. Stabilizing Natural Selection nature selects those with average traits to survive, extremes die Normal variation of spiders w/ no predators 2. Directional Natural Selection nature selects those with one extreme variation in trait to survive, average trait & other extreme creatures die Normal variation of woodpecker beaks w/ no natural selection small average Size of spiders 3. Diversifying Natural Selection nature selects those with both extremes (big & small) to survive, those with average traits die Normal variation of shellfish w/ no predators white color small tan average Size of beak Color of shellfish large large brown color Variation of spiders w/ selection for average size (birds eat large, small can t get food) ) Variation of beak size w/ nature selecting for ability to get food (long beaks can get more food in bark) Variation of shellfish color w/ selection for extreme colors (birds eat average color on light rocks & on dark rocks)

3 Habitat: where an organism actually lives Niche: what the organism s job is in that area How does one species evolve into two species (Macroevolution)? Isolation & Change in Environment leads to speciation Ecological Niche -the role or job of an organism in an environment -range of conditions & resources within which the organism can live (real niche never as big as it could be due to competition) Types of Species in an Environment 1. Native species that normally thrive in that ecosystem 2. Nonnative migrate into or accidentally or intentionally introduced (exotic) by humans 3. Indicator sensitive species that provide early warning of ecosystem problems (their # s go down before other species) 4. Keystone species plays vital role to ecosystem (ex. pollinators) 3 Basic Types of Species Interaction 1. Interspecific Competition competition between members of two or more different species for food, space, or any other limiting resource Competitive Exclusion similar species cannot occupy the same niche indefinitely, one species eliminates the other through competition for limited resources The Green Anole is from Florida. (green niche) When the brown Anole was introduced from Cuba it first overlapped the niche of the Green Anole. But according to Competitive Exclusion, the larger Brown Anole overtook part of the Green s niche. How do species reduce competition? Resource Partitioning

4 dividing up resources by using at different times, different ways, different places. ex. Owls & hawks -similar prey but hawks feed/day and owls feed/night Lions & leopards -similar prey, but lions/larger prey & leopards/smaller prey 2. Predation one species (predator) feed directly on living organism of another species by pursuit or ambush (removes weakest of prey from population) since predators must assess prey during pursuit or stalking, their brains are usually larger than prey animals camouflage Ways to avoid predation warning coloration of poison chemical warfare deceptive looks & behaviors travel in schools or herds shells, speed, flight, smell 3. Symbiosis relationship in which species live together in an intimate association a. Parasitism parasite benefits & host harmed similar to predation but parasite is usually smaller than host, gradually weakens host, & rarely kills host b. Commensalisms one species benefits & host doesn t care c. Mutualism both species benefit ex. nutritional mutualism Lamprey Orchid + fish + tree

5 lichens (fungus + blue-green cyanbacteria) legume root nodules (N2-fixing bacteria+ plant root) Succession Clownfish + sea anemone natural changes & species replacement in an ecosystem over time 1. Primary (1o) Succession (100s-1000s of years) succession that describes the order of plant & animal species takeover on new land that starts as rock (slowly weathered into soil) ex. Pioneer Species a. Bare rock is exposed. b. Since there is no soil, LICHENS are first to appear since they can live on rocks c. Lichens SLOWLY dissolve rock into sand d. Plants die & become humus & allow rooted plants to grow e. Small plants first, then big ones take over 4. Secondary (2o) Succession ( years) succession that describes the order in which animals & plants will grow on existing land that is destroyed by natural disaster, or farming, etc. o MUCH FASTER than 1 succession because environment does NOT start with bare rock (there is already soil there) Ex. Yellowstone burns down 1988 (abandoned farms another example) a. Flowers take over first b. Shrubs and bushes second

6 c. Pine saplings return d. park returns to climax community of tall pines & hardwoods Species Richness = the # of species in a community varies from one habitat to another (coral reefs & rain forest = high richness) usually greatest at ecotone ecosystems (transition zone between 2 zones) isolated islands & mountaintops have least richness too few niches the richer the community = more stable (loss of one organism doesn t affect whole community) & provide more ecosystem services Ecosystem services