Day 22 April 17th Chapters 14 + 15

Scheduling Issues

Classes Left

• 4/19 – Today – CH 14+15• 4/24 – Chapter 16• 4/26 – End CH 16, Study Guide and

Clicker Review• 4/30 – FINAL EXAM

15.3 Global air circulation patterns create deserts and rainforests.

Is it warmer or cooler in urban areas relative to nearby rural areas?

“Urban Heat Islands”

Asphalt, cement, and tops of buildings absorb heat, raising the temperature.

Why is it so windy on streets with tall buildings?

Which place would you expect to have the highest temperature during the summer?

1. Denver, Colorado (the mile high city)2. Dallas, Texas (large city)3. Farmer’s Branch, Texas (small town

outside of Dallas)4. Freeport, Maine (small town)

Which place would you expect to have the highest temperature during the summer?

1. Denver, Colorado (the mile high city)2. Dallas, Texas (large city)3. Farmer’s Branch, Texas (small town

outside of Dallas)4. Freeport, Maine (small town)

15.6 Energy flows from producers to consumers.

Chains or Webs?

Food chain• Pathway from photosynthetic producers through

the various levels of animals

Food web• Involve harvesting energy from multiple stops in

the food chain

omnivores

15.7 Energy pyramids reveal the inefficiency of food chains.

10% Efficiency

Why are big, fierce animals so rare? And why are there so many more plants than animals?

Biomass

10% rule – what happens to a five lb meal?

Where does the rest go?

Expended in cellular respiration or lost as feces

In humans, why is vegetarianism more energetically efficient than meat-eating?

The 10% Rule in Application

Millions of kilograms of grain can support only a few top carnivores.

You go out to eat at a fancy restaurant. You have a salad, salmon, and for dessert ice cream! Which part of the meal was the most energy efficient food for you to eat?

1. Salad 2. Salmon3. Ice cream 4. 2 and 3

You go out to eat at a fancy restaurant. You have a salad, salmon, and for dessert ice cream! Which part of the meal was the most energy efficient food for you to eat?

1. Salad 2. Salmon3. Ice cream 4. 2 and 3

15.9 Interacting species evolve together.

Natural Selection

Causes organisms to become better adapted to their environment

Does not distinguish between biotic and abiotic resources as selective forces

Penicillin was first isolated from a fungus growing on a plate of bacteria. This is an example of an adaptation of the fungus to fight off the bacteria. This interaction could be described as:

1. coadaptation.2. coevolution.3. symbiosis.4. predation.

Penicillin was first isolated from a fungus growing on a plate of bacteria. This is an example of an adaptation of the fungus to fight off the bacteria. This interaction could be described as:

1. coadaptation.2. coevolution.3. symbiosis.4. predation.

More than just a place for living, a niche is a complete way of living.

“You can’t always get what you want.”

Fundamental niche• the full range of environmental conditions under

which a species can live

Realized niche• where and how a species is actually living

Example - the rats of Boston

15.11 Competition can be hard to see, but it still influences community structure.

15.12 Predation produces adaptation in both predators and their prey.

Predation

One of the most important forces shaping the composition and abundance of species in a community

Predation—an interaction between two species in which one species eats the other

Predation, though, isn’t restricted to the obvious interactions involving one animal chasing down and killing another. Herbivores eating leaves, fruits, or seeds is a form of predation, even though it doesn’t necessarily kill the plant. And predators are not necessarily physically imposing. Each year, more than a million humans die as a result of disease from mosquito bites, compared with fewer than a dozen from shark attacks.

Why do exotic species often flourish when released into novel habitats, even though natural selection has not adapted them to this new environment?

Low Predation Risk

Prey Adaptations for Reducing Predation

There are two broad categories of defenses against predators:

• Physical

• Behavioral

1) Mechanical Defenses

adaptations such as the sharp quills of a porcupine, the prickly spines of a cactus, the wings of a bird or bat, or the tough armor protecting an armadillo or sow bug. These features, as well as claws, fangs, stingers, and other physical structures, can reduce predation risk.

2) Chemical Defenses

Extremely important to plants, that can’t run away

3) Warning Coloration

Top – Monarch Butterfly (poisonous)Bottom – Viceroy Butterfly (non-poisonous)

4) Camouflage

Behavioral Defenses

Include both seemingly passive and active behaviors: hiding or escaping,

or alarm calling or fighting back

Why don’t predators become so efficient at capturing prey that they drive the prey to extinction?

The “Life-dinner Hypothesis” - When a prey, such as a rabbit, for example, can’t escape from

a fox, the cost is its life—and it will never reproduce again. On the other hand, when a fox can’t keep up with a rabbit, all it loses is a meal; it can still go on to capture prey and reproduce in the future. In other words, the cost of losing in the interaction is much higher for the rabbit.

15.13 Parasitism is a form of predation.

Parasite Predators

Parasites have some unique features and face some unusual challenges:

• The parasite generally is much smaller than its host and stays in contact with the host for extended periods of time.

• Complicated life cycles as means of getting from host to host.