Another dimension of Biodiversity is how recognizable associations of organisms inhabit the same place as ecosystems

Transcription

1 ECOLOGY

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

3 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 endosymbioticcyanobacteria), also feed on small animals in water (zooplankton) -grow clonally, plant-like -deposit a bone-like calcium carbonate (CaCO3) structure keeps them near surface the reef

4 Can build huge shelves of coral offshore barrier reefs

5 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 growingcoral with an open lagoon in its center. The process of atoll formation may take as long as 30,000,000 years to occur.

6 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

7 Some contribute to reef building (CorralineAlgae), 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:

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

9 -diverse & unique aquatic & terrestrial community

10 -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

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

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

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

14 -tidal, tide pools Rocky intertidal systems worldwide, similar but different species

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

16 Open Ocean

17 Deep Sea

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

19 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)

20 -So should be all kinds of stuff in seawater (there is, but mostin 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 NaCl (Ca - Foramnifera, Si -Diatoms)

21 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 5x 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 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

22 Salt important for currents affect, salinity varies across globe (but composition constant, variable concentration) Global warming increasing tropical salinity higher evaporation, affect ocean currents

23 Terrestrial Systems Deserts

24 Grasslands

25 Forests

26 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?

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

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

29 Peel the Orange

30 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. Community Pop 1 Pop 3 Ecosystem Pop 2 Abiotic Environment Ecosystems not clearly bounded, generally linked to each other The Biosphere is the aggregate of all linked ecosystems of the earth.

31 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

32 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)

33 Organisms 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).

34 Organisms Predator senses

35 Organisms Prey defenses

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

37 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:

38 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

39 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.

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

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

42 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

43 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.

44 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

45 Populations Flocks, herds gathering Safety in

46 Populations Cooperative hunting

47 Populations Food Social Defense against Role differentiation hierarchies

48 Populations Role differentiation Eusocial queens, workers, soldiers

49 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

50 Populations 2-12/2-13

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

52 Populations Precipitation Temperature

53 Populations The niche of a given species is also shaped by interactions with can limit the niche MacArthur s Warblers classic example of similar species utilizing similar habitat. Competition between individuals of different species possible. 4-3/4-1

54 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