Ecology Ecology the study of the interactions between

Ecology

� Ecology - the study of the interactions between organisms and between the nonliving parts of the environment. � Ecologists – collect data, look for patterns, and explain patterns within the environment

Ecological Issues � Global ◦ warming CO 2 accumulates in the atmosphere. This acts like a blanket to keep heat in, instead of going into space. � This is the green house effect. ◦ This is changing weather patterns and raising sea levels due to melting of polar icecaps.

Ecological Issues � Overpopulation ◦ Overcrowding ◦ Need for: food, shelter, water, energy, and space to dispose of waste. ◦ All of these take more of our natural resources

Ecological Issues � Ozone layer thinning ◦ Keeps out ultraviolet light ◦ More sunburn and skin cancers ◦ CFCs (chlorofluorocarbons) – propellants in aerosol cans

Ecological Issues � Sixth Mass Extinction ◦ Species becoming extinct because of: habitat destruction, over hunting, disease, and predators ◦ If Earth losses the variety of species, disease will occur and less food will be available

Organization of Life � Biosphere – ◦ Thin volume of air and earth where all living things exist ◦ 13 miles below Earth to 5 -6 miles into the atmosphere � Ecosystems – ◦ Divisions of the biosphere (ex. Ponds, lakes, forest, desert) ◦ Includes all living and non-living things

Organization of Life � Communities – ◦ Divisions of ecosystems ◦ Includes only living things ◦ Ex. Fish, turtles, water plants, etc. . � Populations – ◦ Divisions of communities ◦ A population is only one interbreeding species

Organization of Life � Organisms – ◦ Divisions of populations ◦ Individual ◦ What adaptations do they have to survive? � Organ systems – ◦ Circulatory ◦ Digestive, nervous, etc…

Organization of Life � Organs – � Tissues – ◦ Stomach, liver, heart, skin, etc… ◦ Muscles, nervous � Cells – ◦ Smallest unit of life

Some Niches are an Environment 1. ◦ ◦ ◦ Producer Autotrophs make their own food by: 1. Photosynthesis – green plants 2. Chemosynthesis – bacteria Terrestrial producers (land) � Trees, grasses, plants Aquatic producers (water) � phytoplankton

Some Niches are an Environment 2. ◦ Consumer Heterotroph must eat food to get energy (or organic waste) a) Herbivores � � Eat only plants (producers) 1 st order in primary consumers b) Carnivores � � Eat only meat 2 nd or higher order consumer (secondary)

Some Niches are an Environment c) Omnivore �Eat meat and plants � 1 st or higher order consumer d) Detritivores (saprophytes) � Eat dead organisms, waste, fallen leaves, branches, etc. . � Example: vultures, flies e) Decomposers � Break down food and waste and return nutrients to the soil � Example: bacteria, fungi

Some Niches are an Environment � Survival depends on availability of resources and suitability of the environment ◦ Resources – food, water, energy, nesting sites, etc… ◦ Habitat – where organisms live ◦ Niche – role in the environment or way of life �Parts of their role: 1. 2. 3. 4. 5. Range of tolerance Methods to obtain food Number of offspring Time of reproduction Interactions with other species

Some Niches are an Environment � Fundamental Niche (Broad) ◦ Range of conditions that a species can potentially tolerate and range of resources it can potentially use � Related Niche ◦ Range of resources mostly used � Generalist ◦ Species that have a broad range of tolerances with a variety of resources � Specialist ◦ Has a specific resource it only uses. ◦ Examples: Koala Bear, Panda

Some Niches are an Environment � Some animals can be both: ◦ Pacific salmon �Conformer for temperature �Regulator for salinity � Some organisms escape unsuitable conditions 1. Survive unfavorable conditions � Example: animal buries in ground when it is too cold or too dry 2. Dormancy – Reduced activity � Example: broad-leafed trees, hibernation 3. Migration – move to a more favorable area

Some Niches are an Environment � Acclimation ◦ organisms adjust their tolerance to abiotic factors. ◦ This occurs within the life of the organism. ◦ Not an adaptation �Adaptations occur over generations to a population � Conformers ◦ Organisms that do not regulate their internal environment ◦ They change as their external environment changes (coldblooded) � Regulators ◦ Use energy to control some of their internal environment

Factors in an Ecosystem 1. � Abiotic – non-living factors a) b) c) d) e) f) g) h) i) j) Temperature Elevation Humidity p. H Sunlight Soil/rocks Salt contents O 2 levels N 2 levels in soil Water These factors affect what organisms live in a given area

Factors in an Ecosystem 2. Biotic – living factors a) b) c) d) e) producers green plants Herbivores - goats, cows, zebras Predators (carnivores) - leopards, lions Parasites - ticks, tsetse flies, mosquitoes. Decomposer - mushrooms, bacteria, worms etc…………………

Tolerance Curve Cannot tolerate, non -active Tolerates environmental factors Some tolerance, some activity

Tolerance Curve � Some organisms can tolerate extreme heat or extreme cold, but not both � Some times only one factor determines tolerance, but often it is a combination of factors

Food Chain �A single pathway for nutrients to travel � The nutrients go back into the soil

Food Chain � Primary Consumers � Secondary Consumers � Third order consumers ◦ rabbits, squirrels, mice, seed-eating birds, herbivorous insects ◦ Foxes, Hawks and owls, snakes, toads, predaceous insects, insectivorous birds ◦ snakes, hawks and owls, foxes

Food Chain � Energy is not recycled in the food chain � If an animal eats the plant, only 10% of this is used to build new animal tissues. The rest is used by the animal to stay alive, keep warm and move about � This is a chain reaction from producer, to primary consumer, to secondary consumer, etc. .

Food Chain – Pyramid of Energy

Pyramid of Numbers � In a community, as you go down the food chain, the number of each organisms at each level will decrease. � The energy decreases down a food chain so less animals can be supported � Animals also get larger as you move down the food chain

Pyramid of Biomass � As you move down the food chain, the number of organisms decreases, so the total mass per level decreases

Relationships in the Ecosystem � Relationships symbioses are termed symbiotic or ◦ These are two different species that interact with each other � Some relationships help organisms survive � Some relationships make it difficult to survive

Relationships in the Ecosystem 1. Parasitism (harder for host to survive) ◦ A parasite lives off a living organism or host ◦ Takes nourishment from the host �Examples: �ectoparasites – live on outside of host �Ticks, fleas, lice, leeches, lamprey, mosquitoes �Endoparasites – live inside of host �Tapeworms, roundworms, flatworms, fungi, microscopic protists ◦ Host’s adaptations: skin, chemical defenses (tears, mucus, saliva) ◦ Parasite adaptations – develop special structures and functions such as mouth parts

Relationships in the Ecosystem 2. ◦ ◦ ◦ Mutualism Makes it easier for both species to survive Relationship which benefits both species Example: lichen (fungus and algae live together), pollinators (bees, butterflies, etc. . ) � 3. ◦ Animal gets food plants get pollinated Commensalism One species benefits and the other is unaffected � Ex. : orchids in the tropical forest, egrets follow cape buffalo (buffalo stir up grass and egrets eat insects, etc. . )

Relationships in the Ecosystem 4. Competition ◦ Two different organisms compete for the same resources ◦ Makes it harder to survive ◦ Plant example: sunlight, water, growing space ◦ Animal example: food, territory, shelter, mates, water ◦ Competition increases with more closely related species

Relationships in the Ecosystem ◦ Competitive Exclusion �One species is eliminated from an area by a stronger species �Example: �Some plants release toxins to prevent other plants from growing near them �Consume so much there is non left for other organisms �Some organisms adapt by evolving into different niches or develop anatomical differences

Relationships in the Ecosystem ◦ Resource Partitioning �Some animals are closely related but get their food from different sources �Example: warblers 5. ◦ Predation (survival is different) EX. – Wolf and caribou � Wolf eats caribou and benefits by obtaining food � Caribou benefits by removal of weak and sick, which makes herd stronger � This controls population so more resources are available

Relationships in the Ecosystem ◦ Predation Adaptations �Camouflage – able to blend into environment �Heat sensors of snake to accurately strike �Spider webs �Sharp teeth ◦ Prey Adaptations �Fleeing �Camouflage �Bright colors = poisonous �Mimicry – harmless species resemble poisonous or distasteful ones �Ex. – Viceroy butterfly mimics monarch because the taste bitter

Relationships in the Ecosystem ◦ Herbivores vs. plant is a predator vs. prey relationship �Plant’s defenses: thorns, spines sticky hairs, tough leaves, and secondary chemicals that release poison, are irritating, or taste bad �Secondary chemicals can have benefits to humans (medicines) �Morphine, codeine, atropine