Bio 5

Species interaction

Positive, negative, or neutral. Involves feeding and symbiosis

Symbiosis

species that lives in or on another species

Amensalism

One participant is harmed, but other is not affected

Commensalism

positive interaction where one participant benefits and the other is not affected

Mutualism

Positive interaction that benefits both

Predation

Includes carnivory, herbivory, and parasitism.

Coevolution

• Predators evolve strategies to capture prey

• prey evolve strategies to avoid predation

Predation strategies

1. Active pursuit

2. Ambush

Prey defense mechanisms

1. morphological (spines)

2. cypsis (camouflage)

3. alarm calls

4. chemical defense (toxins)

mimicry systems

Both species contribute to predator education

Batesian mimicry

mimic cheats by looking like the model, compromising predator education

Plant defenses against herbivory

Thorns or chemicals, can be resistant from herbivores

Coevolution

Species can evolve to look different than the species that tries to mimic them

microparasites

bacteria, viruses, protists. Live and reproduce inside host. Can cause symptoms of disease

Macroparasites

1. ectoparasites

2. endoparasites

ectoparasites

live outside of body of host

endoparasites

live inside the body of their host

Intraspecific competition

Limit K in population growth

Interspecific competition

among different species can affect each species population growth

Competitive exclusion

Can limit growth of species with competition of a single limiting resource.E

Exploitation competition

All species reduce the quantity of their shared resource

Interference competition

Species 1 directly interferes with or excludes species 2’s access to the limiting resource

Resource partitioning

Different species share different part of the same resource

Outcome of competition can change by other factors

1. physical environment

2. disturbances

3. predation

Fundamental niche

Physical conditions where a species live

Realized niche

part of the fundamental niche where a species can live based on interactions with other species

Mutualism types

1. obligate (required)

2. facultative (optional)

Positive interactions

More common in more intensive environments

Types of communities

1. taxonomic affinity

2. guild

3. functional group

Food webs

represent the trophic or energetic connections in a community

Diversity

Richness + eveness

Shannon index of diversity

Used to estimate species diversity. Must flip sign at end

How to species come together and form distinct communities

Filters

What does community membership depend on

Regional species pool, dispersal, abiotic conditions, and biotic conditions

Direct interaction

A → B

Indirect interaction

A → B, B → C, A → C

Trophic cascades

have consequences in species abundance from higher to lower trophic levels

Keystone species

Can make or break their community despite their population. Have economic and cultural value

Foundation species

Provide habitat and food for species

Ecosystem engineers

Beavers, can be both keystone or foundation species. Engineer the environment

Disturbance

an abiotic event that physically or chemically injures or kills individuals, creating opportunities for others to grow and reproduce. Small or large

Community succession

Change in the community species composition over time following a disturbance

Primary succession

Starts with no plants or soil. A lot longer

Moraine

gravel deposit at glacial front

Climax community

mature, stable final stage of ecological succession

Secondary succession

Retains soil and some organisms after disturbance, a lot faster

Facilation

The presence of one species increases the probability of the second species becoming established

Inhibition

The presence of one species decreases the probability of the second species becoming established; first come first serve

Alternative states

Whole new community forms at the same location after a disturbance

Diversity benefits

1. more resistance to disturbances

2. better limiting resource use

Monoculture

less productive and less stable (1 crop)

polyculture

More productive and more stable (many crops)

Primary production (energy flow)

photosynthesis and chemosynthesis

Secondary production (energy flow)

energy for consumers in food webs

Nutrient cycling

macro and micronutrients move through organisms and the physical environment

NPP

net primary productivity biomass incorporated to the tissues of primary producers after respiration

GPP

gross primary productivty is the total carbon fixed by primary produces

respiration

gs exchange/metabolic needs

NPP trends

1. higher in 0 latitude

2. higher in land

3. tropics

4. higher in northern hemispehere due to more land

5. more southern hemisphere

NPP effects

1. High rainfall and high sunlight = high NPP

2. high rainfall and low sunlight = lower NPP

3. co2 also and temperature importanant

Woody biomass

plant material from trees and shrubs, including roots, bark, leaves, trunks, branches, and vines

Factors in the sea for NPP

1. coral reefs and algal beds have high NPP

2. light and nutrients drive these

Consumption efficiency

proportion of the available biomass ingested by consumers

assimilation efficiency

is the proportion of the ingested biomass that consumers assimilate by digestion

Production efficiency

proportion of assimilated biomass used to produce new consumer biomass

Endotherms

use most assimilated energy to maintain a constant body temperature

trophic efficiency

The amount of energy at one trophic level divided by the amount of energy at the trophic level immediately below it. Higher in aquatic

Top-down control

consumption determines NPP (keystone)

bottom-up control

resources determine NPP (upwelling)

NPP in trophic levels

1. more NPP means longer webs

2. shorter food webs recover faster in disturbances

3. top predators are not predated, limiting how long the food web is

Provisioning services

products

Regulating survices

control of disasters

supporting services

soil, carbon, and nutrients

cultural services

recreational activities