BIO 111 - Unit 5: Module 1 (Ecology)

What is Ecology?

The study of how organisms interact with each other and their environment

What is organismal ecology?

- The study of individual morphological, physiological, and behavioral adaptations

- How individuals interact with each other and their physical environment

Functions of animal communication

Signal from one individual modifies the behavior of a recipient individual

- Sender: Individual making the signal

- Receiver: Individual responding to signal

ex: ground squirels tail flagging/snakes heat detection

What is Population ecology?

Study of the number and distribution of individuals in a population over time

What is a population?

A group of interbreeding (or potentially interbreeding) individuals of same species in same area (at same time)

What are life history trade-offs?

- Limited resources (and time) lead to fitness trade-offs in resource allocation to growth, reproduction, survival

- universal, but the best strategy is different for different species

R-selected species

- Grow quickly

- small adults

- short lifespan

- Reproduce early in life

- Produce many offspring, low investment in each

- Few of which survive to adulthood

ex: mice

K-selected species

- Grow slowly

- large adults

- long lifespan

- Reproduce when older

- Produce few, expensive offspring (and often care for them to ensure survival)

ex: humans, elephants

What is Community ecology?

Study of the nature of the interactions between different species in a community

− Species interactions

− Community Structure

− Community Dynamics

What is a community?

All the populations of different species that are interacting in a certain area

What defines species interaction?

Defined by whether the species in the interaction incurs a fitness cost (-) or gains a fitness benefit (+) or is unaffected (0)

What do species interactions do?

- Affects distribution/abundance of a species

- Coevolution can occur during interactions

- Outcome of interactions is dynamic and conditional

Consumption (+/-) / types of consumption

One organism eats part or all of another

Types:

1. Predation: A predator kills and eats an animal

2. Herbivory: An herbivore eats a plant

3. Parasitism: A small organism eats small amount of host tissue

Defenses against consumption (Mimicry)

- Evolution favors sending signals to predators to avoid getting eaten (Aposematic coloration)

- Predators are more likely to recognize a signal if it is common

- Batesian mimics: look dangerous, are not dangerous

- Müllerian mimics: look dangerous, are dangerous

Predator adaptations

- Weapons

- Deception

- Hunting in groups

- Eavesdropping

What is the coevolution arms race?

What is Ecosystem ecology?

Study of nutrient and energy movement among organisms and

surrounding atmosphere/soil/water

What is an ecosystem?

- Community of interacting species present in a region, along with the abiotic components of the soil, water, and atmosphere

- Everything is linked to everything else by flow of energy and nutrients

Trophic structure

- Trophic Level: Organisms all obtaining energy from the same type of source

- Food chains become food webs to account for complexity