ECOLOGY Another dimension of Biodiversity is how

ECOLOGY

Another dimension of Biodiversity is how recognizable associations of organisms inhabit the same place – as ecosystems Understanding these associations is the subject of Ecology

For example, coral reefs are distinctive aggregations of species found on some tropical coastlines. The reefs themselves are built by animals - the reef building corals (Phylum Cnidaria, Class Anthozoa, Order Scleractinia) - photosynthesize (via endosymbiotic cyanobacteria), also feed on small animals in water (zooplankton) - grow clonally, “plant-like” - deposit a bone-like calcium carbonate (Ca. CO 3) structure – keeps them near surface – the “reef”

Can build huge “shelves” of coral offshore – “barrier reefs”

Or other forms, e. g. Atolls This animation shows the dynamic process of coral atoll formation. Corals (represented in tan and purple) settle and grow around an oceanic island, forming a fringing reef. In favorable conditions, the reef will expand, and the interior island will subside. Eventually the island completely subsides beneath the water, leaving a ring of growing coral with an open lagoon in its center. The process of atoll formation may take as long as 30, 000 years to occur. http: //en. wikipedia. org/wiki/Atoll

Coral reef systems are very diverse – many other species live in and around reef Various reef systems around the world, contain different species, but similar mixes of types – readily classified as “coral reefs”

Some contribute to reef building (Corraline Algae), some just live there (shrimp, crabs, fish), some even eat coral and damage the reef (Polychaetes, sponges, starfish). If this is a “system”, what kind of system is it? Nice tour: http: //www. biosbcc. net/ocean/marinesci/04 benthon/crzone. htm

In other tropical coastal areas – Mangrove swamps - coastal forests, held together by tree roots - specialized salt water tolerant trees

- diverse & unique aquatic & terrestrial community

- Mangrove not a taxonomic group, various groups – all “converged” on similar adaptations – e. g. “_______” - Mangrove systems throughout the world, different species, similar mix of types – readily classified as “Mangroves”

Red – coral reefs, Green – Mangroves, Blue – Lakes, Rivers, Ocean

Bare rock shores - “rocky intertidal” system - “simple” communities, few species

- seaweeds (algae), barnacles, mussels, snails, starfish

- tidal “____”, tide pools Rocky intertidal systems worldwide, similar but different species

Coastal Salt Marshes - river enters sea – “estuaries”, mix of salt and freshwater - extensive stands of plants, many organisms

Open Ocean

Deep Sea

Fresh Water systems Rivers, streams, lakes, ponds, marshes

By the way, why ARE oceans salty? The hydrologic cycle- Water evaporates, leaves salt behind Salts are dissolved ions Ions come from ____ weathered by rain 2. 2 lbs of it for every cubic foot of seawater (taken out and spread across land – 500 ft thick)

- So should be all kinds of stuff in seawater (there is, but most in very small amounts, e. g. gold) - Should be like concentrated ______ water – but it’s not – why? >85% is sodium & chloride (Na+, Cl-) – table salt, also (Mg, S, K) - Life alters ocean chemistry - organisms remove a bunch of things but NOT Na. Cl (Ca - Foramnifera, Si - Diatoms) http: //www. palomar. edu/oceanography/salty_ocean. htm

Of course we went for a float in the water. This is a must do for anyone coming to Israel. The water in the Dead Sea is some 5 x more salty than sea water. In addition, it is laden with many other minerals. The Israelis claim soaking in its waters is healthy and is a good treatment for any skin problem. When you climb in, you can feel the buoyancy immediately. You feel oily and realize that you're not walking over sand but salt. It tastes really bad and you can see minerals precipitating out of the water. Along the beach is a white crust of salt. We drove for a while down the other side of the sea where they harvest the minerals and it actually makes the water look pretty disgusting. Anyway the water is incredibly buoyant. Everyone just floats on top of the water. It's so buoyant that you can spin or lift your leg out of the water. You're only supposed to soak 20 -30 minutes so we also did some quality lazing on the beach which was a nice break. There was the guy who panicked in knee deep water and thought he was drowning until he stood up. . . in knee high water. The new sensation of super buoyancy was a blast and the most fun I have had wading about in years. It made me feel like a little kid again – Michael Kan http: //www. kan. org/michael/mideast 3. html

Salt important for currents – affect ____, salinity varies across globe (but composition constant, variable concentration) Global warming increasing tropical salinity – higher evaporation, affect ocean currents http: //www. whoi. edu/institutes/occi/currenttopics/abruptclimate_rcurry_pr_en 1. html

Terrestrial Systems Deserts

Grasslands

Forests

Patterns – simple questions - diverse species why so many? why not just one? - species limited in distribution why here, not there? why not same species everywhere? - mixture of kinds of species (bacteria, plants, fungi, animals) how do they coexist, interact? - characteristic assemblages (convergence) – different species, but similar why particular associations? - found in similar types of places, similar climates what is role of environment?

What is “Ecology”? The study of biological organization “at and above the level of the organism”. (one definition) Ecology What are “_________”? Biosphere Ecosystem Community Population Organism Organ Tissue Cell Organelle Molecule 2 -7

Ecosystem Community Population 1 Abiotic Environment Light, nutrients, substrate, etc. Pop 2 Pop 3 etc. Organism (sp. 1) 2 3

Peel the Orange

So “_____” refers to all the Organisms of different species living in the same place as well as the non-living part of the Environment they utilize and live in. The organisms exist as ______ – multiple members of a species, that interact with other populations to form a ____ – the array of interacting populations in a place. Ecosystem Community Pop 1 Pop 2 Abiotic Environment Pop 3 Ecosystems not clearly bounded, generally linked to each other The Biosphere is the aggregate of all linked ecosystems of the earth.

The term ______ refers to widespread ecosystem types (generally terrestrial) such as “deserts”, “grasslands” etc. So “biome” is more of a category rather than a “real” thing. The equivalent in aquatic systems is ______ (such as lakes, streams, open ocean, coral reefs, estuaries, etc. ) 3 -5/3 -6

Ecologists study emergent properties of all these levels Organism – ______, time budget Population – growth rate, carrying capacity Community – diversity, ______ Ecosystem – _____, nutrient cycling Biosphere – ______, atmosphere Study at any particular level usually requires simplification of the lower/deeper levels Biosphere Ecosystem Community Population Organism Organ Tissue Cell Organelle Molecule _______ is studied at multiple levels genetic (population), species (community), functional (ecosystem), habitat (“landscape”, biosphere)

Organisms are “organized” for ecological success Genomes, organ systems, physiology, growth, behavior, etc. are highly integrated to serve the survival and reproduction of the ________ (fitness).

Organisms Predator senses

Organisms Prey defenses

Organisms Plants in the desert are adapted to reduce water loss Or no leaves Small, thick leaves Or store it

Organisms Many desert animals (esp. seed eaters) never drink Various adaptations to reduce water loss (reduced urine, feces, etc. ) But where do they get it? Read more: http: //www. desertusa. com/survive. html

Organisms Integrated organisms, the autocatalysts, are the basic components of processes at the higher levels. Analogous to “individuals” in economic theory. Individuals determine processes at higher levels – but they don’t, can’t, exist ________

Populations What “organizes” biology above the level of the organism? At the population level – mainly ___________. Population – all the individuals of the same species in the same place, generally with the potential to __________. _______ – the sum of all populations of a species – defines the distribution of a species in space.

Populations are _____ – inputs and outputs Population growth = Inputs (births, immigrants) – outputs (emigrants, deaths) Growth has ______ potential, but growth _______ as population increases – “carrying capacity” Carrying capacity - Competition resource depletion agonistic interactions - Increased enemies - “density dependent” 4 -7/4 -5

Density ______factors - Real populations bounce around a lot, within bounds - Environmental fluctuations – climate, food, enemies - Can lead to population extinction, esp. small pops

Populations Population regulation important for _______ - species extinction, protection – “_____” - species introductions – “_______” - species harvest – “________ yield” Harvest – growth curves imply maximum growth at ______ population densities - too low, few individuals to reproduce, despite high reproductive capacity - too many (near carrying capacity), low reproductive capacity per individual. Pop Growth Density

Populations ________ – populations distributed in space Population viability may depend on other nearby populations that share migrants “Sources” vs. “Sinks” - any particular population may appear healthy, but may depend on healthier population nearby.

Populations Sociality In animals, populations may be subdivided into social groups Key feature – ______ – conspecifics (members of the same species) acting in concert to increase success (fitness). “______ amongst competitors” – helping behaviors evolve through direct benefits and reproductive benefits Two main benefits – _____ and _____ often social groups benefit in both temporary or permanent often internal structure - dominance hierarchies - “eusociality” – caste systems

Populations _____ gathering Safety in ______ Flocks, herds

Populations Cooperative hunting

Populations Food ____ Social ______ Defense against ______ Role differentiation – _____ hierarchies http: //www. discoverlife. org/ap/

Populations Role differentiation Eusocial _____ – queens, workers, soldiers

Populations The Niche Concept Goal - to understand the distribution and abundance of individuals of a species (populations) in space and time (another definition of ecology) Traits of each species determine success or failure The characteristics of the environment where a particular species succeeds define its niche – includes both _____ and _____ components Climate (temperature, moisture, etc. ) Resources (food, reproductive sites, etc. ) Predators, diseases, etc. Major idea – Niche – ecological limits of a species - map of organisms in physical space/time to ________

Populations 2 -12/2 -13

Populations Niches are measured and depicted graphically on niche axes axis – dimension of ecological space Niches may be broad, narrow, overlapping, Axis B and ________ Axis A

Precipitation Populations Temperature

Populations The niche of a given species is also shaped by interactions with ________ can limit the niche “Mac. Arthur’s Warblers” – classic example of similar species utilizing similar habitat. Competition between individuals of different species possible. 4 -3/4 -1

Populations/Communities Similar species can co-exist more readily if they utilize different portions of shared niche axes – have different niches (determined by traits) Coastal wetland So, an organism’s integrated traits (genes) allow success or determine failure of a population in any particular ecosystem Both the possibilities and limits for survival