EcologyEcology

Chapters 50-55Chapters 50-55

Review of Ecology VocabReview of Ecology Vocab

PopulationPopulation CommunityCommunity EcosystemEcosystem BiosphereBiosphere HabitatHabitat NicheNiche

Population EcologyPopulation Ecology

The study of growth, abundance, and The study of growth, abundance, and distribution of populations.distribution of populations. SizeSize DensityDensity DispersionDispersion

SizeSize

Total number of individuals in the Total number of individuals in the population.population. How are populations counted?How are populations counted?

Random SamplingRandom Sampling

DispersionDispersion

3 Distribution Types3 Distribution Types ClumpedClumped UniformUniform RandomRandom

Age StructuresAge Structures

What is it? What are the types?

www.campbellbiology.com Login:RVRHS2010 Password: reddevil10

7th Edition Chapter 52

52.6 Graph It: Age Pyramids and Population Growth

Answer questions: Email results to me kcsmith@rvrhs.com

Survivorship CurvesSurvivorship Curves Type IType I

Curves describe species in which most individuals Curves describe species in which most individuals survive to middle age followed by high mortality survive to middle age followed by high mortality rate.rate.

Type IIType II Curves describe organisms in which the length of Curves describe organisms in which the length of

survivorship is random.survivorship is random.

Type IIIType III Curves describe species in which most individuals Curves describe species in which most individuals

die young with few surviving beyond reproductive die young with few surviving beyond reproductive age.age.

How do Populations grow?

Biotic Potential The maximum growth rate of a population under

ideal conditions, with unlimited resources and without any growth restrictions.

Factors that Contribute to the biotic potential of a species: Age at reproductive maturity. Clutch size (# of offspring produced at each event) Frequency of reproduction. Reproductive lifetime Survivorship of offspring to reproductive maturity.

How is population growth limited?

Carrying capacity Limiting Factors

Density-dependent Density-independent

Predation factors

Patterns of Population Growth

Exponential Growth Reproductive rate is greater than 0. J-shaped curve

R-selected species: opportunistic species

Logistic Growth Limiting factors restrict the size of the

population to carrying capacity. S-shaped or sigmoid curve

K-selected species: population size remains constant.

Human Population Growth

What are the 4 factors that made exponential growth possible? www.campbellbiology.com Login: Password: Chapter 52: Activity: Human Population

Growth

Community Ecology

Interactions of populations. 3 Forms of interactions

1. Interspecific competition 2. Predation 3. Symbiosis

Interspecific Competition

Competitive Exclusion Principle Resource Partitioning Character displacement Realized Niche

Predation

True Predator Parasite Parasitoid Herbivore

Symbiosis

Mutualism Commensalism Parasitism

Bottle GentianGentiana andrewsii

The "bottle gentian" (or "closed gentian") is an unusual woodland flower -- its common name derives from the fact that its petals never open!   Mature flowers look just like large buds.   Although these flowers produce a rich source of pollen and nectar, most insect pollinators are not able to get inside. Bottle gentians are pollinated almost exclusively by large bumblebees that are strong enough to force.

The Torsalo (or "human bot fly") is native to the New World tropics where it is regarded as a pest because its larvae burrow under skin and live within warm-blooded animals.   Torsalos are the only species of bot fly that invade humans.

An adult torsalo is a rather large insect (10-15 mm) with a bluish-black body, brown wings, and yellow markings on the face and legs.   It is a loud, buzzing flier that tends to attract attention to itself. Ordinarily, such a large, obnoxious insect would have difficulty approaching a large animal to lay eggs.   But female torsalos overcome this problem by catching smaller flies (like mosquitoes) and gluing eggs to the underside of the captive's body.   The captive is released unharmed, carrying the torsalo's eggs until it lands on a warm-blooded host.   Body heat from the host triggers rapid hatching of the torsalo's eggs.   The tiny maggots burrow quickly into the skin (even through clothing) and begin development as internal parasites.

ENTOMOLOGY FOR EDUCATORS, www.cals.ncsu.edu/course/ent591k/symbiosis.html

The Light-Organ Symbiosis of Vibrio fischeri and the

Hawaiian squid, Euprymna scolopes

During the day the bobtailed squid, Euprymna scolopes, remains buried in the sand of shallow reef flats. As the sun sets, the nocturnal animal emerges from its safe hiding place and searches for food. In the moonlit night, the squid would appear as a dark silhouette when it swims through the water and would be easily detected by predatory fish from below. It is thought that the squid camouflages itself by projecting light downward from its light organ. Inside the light organ are luminescent bacteria, Vibrio fischeri, that produce the light.

ENTOMOLOGY FOR EDUCATORS, www.cals.ncsu.edu/course/ent591k/symbiosis.html

An example of mutual symbiosis is the relationship between clownfish of the genus Amphiprion (family, Pomacentridae) that dwell among the tentacles of tropical sea anemones. The territorial fish protects the anemone from anemone-eating fish, and in turn the stinging tentacles of the anemone protect the anemone fish from its predators (a special mucus on the anemone fish protects it from the stinging tentacles).

Wikipedia, http://en.wikipedia.org/wiki/Symbiosis

Goby fish sometimes lives together with a shrimp. The shrimp digs and cleans up a burrow in the sand in which both the shrimp and the goby fish live. The shrimp is almost blind leaving it vulnerable to predators when above ground. In case of danger the goby fish touches the shrimp with its tail to warn it of imminent danger. When that happens both the shrimp and goby fish quickly retract into the burrow.

Wikipedia, http://en.wikipedia.org/wiki/Symbiosis.

A famous land version of symbiosis is the relationship of the Egyptian Plover bird and the crocodile. In this relationship, the bird is well known for preying on parasites that feed on crocodiles which are potentially harmful for the animal. To that end, the crocodile openly invites the bird to hunt on his body, even going so far as to open the jaws to allow the bird enter the mouth safely to hunt. For the bird's part, this relationship not only is a ready source of food, but a safe one considering that few predator species would dare strike at the bird at such close proximity to its host.

Wikipedia, http://en.wikipedia.org/wiki/Symbiosis.

Hermit crabs use gastropod shells to protect their body.

www.afsc.noaa.gov/kodiak/

Photo: www.life.uiuc.edu/.../ Images/orchid_on_bark.jpg

Epiphytic plants (such as many orchids) which grow on tall trees, in order to gain better access to light.

Wikipedia, http://en.wikipedia.org/wiki/Symbiosis

photo: www.punchstock.com/.../ medio/cd_4800115.html

Some birds, like this owl, live in holes in trees.

zentelligence.blogspot.com/ remora.jpg

Remoras travel attached to a shark and share scraps of food missed by their host. The shark doesn’t even seem to notice.

The oxpecker rids the warthog of ticks and obtains food in the process.

www.worldwildlife.org/ windows/images/warthog.jpg

Chalcids are tiny, dark-coloured wasps, often metallic blue or green with complex sculpturing on the body. They are also recognized by the

characteristic reduced wing venation. In a few species the larvae feed inside seeds and stems. Generally beneficial to humans as a group,

chalcids keep crop pests under control, and many species have been imported to control insect pests.

Wikipedia, http://en.wikipedia.org/wiki/Chalcid

A large Australian Garden Orb Weaver Spider. It has captured a bee in its web and has spun it into a coccoon.

Wikipedia, http://en.wikipedia.org/wiki/Image:Garden_orb_weaver05.jpg.

Pitcher plants are carnivorous plants whose prey-trapping mechanism features a deep cavity filled with liquid. Insects such as flies are attracted to this cavity, often by the red-purple color and by the nectar within. The liquid contained within the pitcher traps and gradually dissolves the body of the insect. This may occur by bacterial action, or be due to enzymes secreted by the plant itself. Furthermore, some pitcher plants contain insect larvae, which feed on trapped prey, and whose excrement the plant absorbs. Whatever the mechanism of digestion, the prey items are converted into a 'soup' of amino acids, peptides, phosphate, ammonium and urea, from which the plant obtains its mineral nutrition (particularly nitrogen and phosphorus). Like all carnivorous plants, they occur in locations where the soil is too poor in minerals and/or too acidic for most plants to be able to grow.

Wikipedia, http://en.wikipedia.org/wiki/Pitcher_plant.

photo: http://www.entm.purdue.edu/wildlife/coyote_pictures.htm

Coyotes attack, kill and eat sheep.

Photo: w3.dwm.ks.edu.tw/.../ 51/images/ch51c5.jpg.

Both hyena and buzzards feed from abandoned carcasses.

Primary Succession

Begins in area with no life Pioneer organism such as lichen grow on bare rock

and produce acids which corrode the rock (freezing and thawing of water may help break down rocks)

Mosses begin to anchor in primitive soil and decompose to add to fertility of the soil

Ferns, grasses and shrubs may appear Gradually trees may become dominant (climax stage) Each species changes the environment to some

degree that may enable or inhibit other species to thrive in the area

Lichens are Pioneer Species

Secondary Succession

Occurs when community has been cleared by a disturbance such as a fire

Often area begins then ends into something like its original state

The earliest plants to recolonize are often plant species that grow from windblown or animal-borne seeds

Woody shrubs may later replace the herbaceous species, and forest trees replace most of the shrubs

Secondary Succession

• Early: plants typically small with short lifecycles (annuals…), rapid seed dispersal, environmental stabilizers.

• Middle: plants typically longer lived, slower seed dispersal, and in woodland systems: larger.

• Late: plants and animal species are those associated with older, more mature ecosystem.

• “Climax”?

Abiotic Factors

Abiotic factors: physical environmental factors such as water, temperature, soil and light, that influence the composition and growth of an ecosystem.

Cycling of Materials

Matter (materials) must be recycled if an ecosystem is to continue to function

Many nutrient cycles exist in an ecosystem: carbon cycle, nitrogen cycle, water cycle etc. *Although matter can be recycled, energy is

not cycled and the energy lost is constantly replaced by the energy of sunlight

WaterAll organisms need water; for

example, water is a medium in which many

organisms live, move, and reproduce

an important component of cytoplasm

a reactant needed for photosynthesis

a limiting factor which determines which organisms inhabit an area

Nitrogen cycle Nitrogen in the

atmosphere is in an unusable form: Nitrogen Gas.

Nitrogen fixing bacteria change the nitrogen into a usable form. Soil and on plants.

Nitrogen returns to the atmosphere by a process denitrification (bacteria)

Animals get nitrogen by eating plants.

Carbon cycle Plants take in carbon

through the process of photosynthesis.

Animals eat the plants (consumption) and use the energy to perform cellular respiration.

Factories and cars use fossil fuels (decomposed dead animals) and burn them.

Phosphorus Cycle

Reservoirs: Rocks

Assimilation: Plants absorb

inorganic phosphate from soils.

Animals obtain organic phosphate when the consume

Release: Decomposition. Excretion

Trophic Levels Trophic structure / levels~

feeding steps (relationships) in an ecosystem

Primary producers~ the trophic level that supports all others; autotrophs

Primary (first-order) consumers~ eat producers; herbivores (ex: cow grazing on grass; mouse eating grain)

Secondary (second-order) consumers~ carnivores (ex. snake eating a mouse)

Tertiary (third-order) consumers~ eat secondary consumers (owl eats snake)

Food Chain

An Aquatic Food Web

Food webs~ interconnected feeding relationship in an ecosystem; organisms may participate in more than one food chain.

Energy Pyramid

Pyramid of Energy:

diagram of the transfer of energy in a food chain that shows the energy levels within an ecosystem