Ecology Test 3

Interference competition

Direct form of competition where organisms fight/ block others from accessing shared resources

Exploitative/Resource competition

Indirect ecological interaction where organisms reduce the availability of a shared/ limited resource by consuming/ acquiring it first

Niche partitioning

Process in which ecologically similar species coexist by using different resources or specializing on different factors in the environment

Hutchinsonian Niche

n- dimensional hypervolume containing the set of conditions and resources that would permit a species to grow/ reproduce

Janzen and Connell hypothesis

Explains how high plant biodiversity is maintained in tropical forests

• specialized natural enemies gather near adult parent trees where their specific food source is abundnant

• only seeds that travel a safe distance away from the parent tree have a high probability of surviving

Character displacement

Evolutionary process where two similar, competing species develop distinct traits to reduce niche overlap and coesist

Rank-abundance plot

Chart used in ecology to display the relative abundance and distribution of species within a biological community

Priority effects

Usually the larger/ early-arriving individual has an advantage in strength of species interactions

food webs

Natural network of interconnected food chains that shows how energy/ matter flow through an ecological community

metamorphosis

Biological process where an animal changes its physical body shape/ structure drastically as it grows from a baby into an adult

temporal variation affecting species interactions

Daily temperature cycles/ seasonal phenology/ multi-year rainfall patterns shift ecological roles and drive biodiversity

size-mediated interactions

Strength of species interactions depends on size of interacting individuals

Plant animal interactions influencing culture, economy, conservation, human health

• economy: pollination, agricultural pests

• embedded in distinct aspects of our culture

• mental health

• central to nature conservation

Herbivory

Process where an animal/ primary consumer feeds on living plant material, algae, or phytoplankton

Mutualism

Ecological interaction between two or more different species where every participating species experiences a net fitness benefit

Parasitism

Close relationship between different species where one organism (the parasite) lives on/ inside another organism (the host), getting nutrients at the host’s expense

Plant defense

Physical, chemical, indirect, mutualismEco

Amenalism

Ecological interaction between two different species where one organism is harmed/ destroyed, while the other organism is completely unaffected

• unaffected organism gains no benefit or cost from the interaction

Comensalism

Long-term biological interaction where one species benefits, while the other species is neither helped or harmed

Species rank abundance plots

2D graph used in ecology to visualize biodiversity, species richness, and species evenness

The competitive exclusion principle

Two species competing for the same exact limited resources cannot stably coexist in a constant environment

Hurlbert’s PIE

Measures the probability that if you randomly select 2 individuals from a community, the second individual belongs to a different species than the 1st

• low (close to 0): Individuals are likely to be the same species- one species may dominate the community

• high (close to 1): Individuals are likely to be different species- the community has relatively high diversity and evenness

Species richness

Total count of different species present in a defined community/ ecosystem

Species abudance

Total number of individuals

Alpha diversity

Species richness within one local community (how many species are in this area)

Beta diversity

The total number of unique species across all the local communities being studies (how many species there are across the whole region)

Gamma diversity

Species turnover between communities (How different are the species in one community from those in another?)

Phylogenetic diversity

A measure of biodiversity that calculates the total amount of evolutionary history represented by a set of species, communities, or taxa

Functional diversity

The variety/ range of ecological or functional traits of species present in a community rather than just the number of species

Chan et al. 2019

Climate change can change the type of competition that limits a species’ geographic range

• competition/ abiotic conditions work together to determine where species can survive/ reproduce

Pringle et al. 2019

Predators shifted brown anoles into the green anoles’ habitat, increasing niche overlap and competition and reducing coexistence

𝑑𝑁1/ 𝑑𝑡 = 𝑟1𝑁1 (𝐾1 − 𝑁1 − 𝛼12𝑁2/ 𝐾1)

Population growth rate of species 1 in the presence of a competing species 2

Niche

Set of conditions/ resources that would permit a species to grow/ reproduce

Fundamental niche

Potential set of conditions and resources in which a species could grow/ reproduce

Realized niche

Set of conditions and resources in which a species could grow/ reproduce in the presence of other species