Communities, Dispersion, Succession, and Stability

Question 1

What is a community

Answer 1

Community is a group of interacting organisms constrained in time and space

Question 2

What is community ecology

Answer 2

Community Ecology is the study of changes in the community structure over time and the variation between communities throughout space

Question 3

What are alpha diversities

Answer 3

Alpha diversity studies community diversity within a habitat

Question 4

What are beta diversity

Answer 4

Beta diversity studies community diversity between habitats

Question 5

What is gamma diversity

Answer 5

Gamma diversity is the study of large-scale landscape diversity (alpha and beta); it’s a comparison of diversity between ecosystems.

Question 6

What is the optimal range of tolerance limits

Answer 6

It the optimal environment and the species is abundant

Question 7

What is the zone of physiological stress in tolerance limits

Answer 7

The species is infrequent

Question 8

What is the zone of intolerance in tolerance limits

Answer 8

The species is absent

Question 9

What is the positive interactions for an organism

Answer 9

Positive interactions are something where an organism helps you to grow - you will eventually reach a point where you can’t grow anymore.

Question 10

What are negative interactions for an organism

Answer 10

Negative interactions are something when an organism will negatively impact the growth rate and will possibly kill off an organism

Question 11

How do most organisms live with positive and negative interactions

Answer 11

Because most organisms have a mixture of positive and negative interactions there is typically a good area between positive and negative interactions. There is a maximum growth rate somewhere around the intermediate population.

Question 12

What are competitive exclusion

Answer 12

No two species can occupy the same niche - one will out-compete the other

Question 13

What is resource partitioning

Answer 13

NIches are divided up by the specialization of competing species.

Question 14

What are direct impacts

Answer 14

Direct impact of one individual on another when not mediated or transmitted through a third individual. In other words A (donor) influences C (recipient)

Question 15

What are indirect impacts

Answer 15

Indirect impacts can be defined as the impact of one organism or species on another that is mediated or transmitted by a third. In other words, A (donor) has an effect on B (transmitter) which then affects C (recipient).

Question 16

What is mutualism

Answer 16

When the two species are benefiting from their relationship

Question 17

What is commensalism

Answer 17

When one species is benefiting from the relationship, while the other has no impact on the relationship

Question 18

What is predation

Answer 18

When one species is benefiting from the relationship at the detriment of the other species. This is typically when the larger species is doing the harming

Question 19

What is herbivory

Answer 19

When one species is benefiting from the relationship at the detriment of the other species. This is typically when a herbivore is benefiting and the herb is not benefiting.

Question 20

What is parasitism

Answer 20

When one species is benefiting from the relationship at the detriment of the other species. This is typically when the smaller species is doing the harming

Question 21

What is amensalism

Answer 21

This is when one species has no affect on the relationship and this other is being disadvantaged

Question 22

What is competition

Answer 22

When both of the species are at a disadvantage

Question 23

What is neutralism

Answer 23

When both the species have no affect on one another.

Question 24

What is biogeography

Answer 24

The study of species geographical distribution

Question 25

How is diversity determined

Answer 25

Diversity is determined by speciation, dispersal, and extinction.

Question 26

What is the neutral model of community assembly

Answer 26

Community structure is based on historical patterns of distribution and abundance. It is not based on traits, does not consider specific interactions between species, and doesn’t consider niches. The organisms from the same trophic level are interchangeable.

Question 27

What is the Z-Slope

Answer 27

Quantitative measure of the strength of the relationship between species richness and area. High Z value means richness is highly response to area. This can be caused by genetic bottleneck, speciation, population size is small, genetic redundancy, and carrying capacity. Contiguous habitat is where there are bridges between habitats

Question 28

What are the conclusions of disperson

Answer 28

Everything seems to be everywhere at lower genetic resolution. The environment selects, but only some factors. Whether is microbial biogeography appears to differ if we are talking about contiguous or island environments.

Question 29

What are press experiments

Answer 29

Disturbance is maintained constantly and it can be direct and indirect effec.ts

Question 30

What are pulse experiments

Answer 30

Perturbation is transient and it is direct effect although some indirect effects can occur quickly

Question 31

What is succession

Answer 31

Succession is the directional and predictable change which a community undergoes over time. These shifts are in the presence and abundance of species. Usually focused on plant species (habitat forming species) but all species are subjected to succession processes.

Question 32

How is succession determined

Answer 32

The process is driven by the interaction between biotic and abiotic factors. Each species colonizers an environment, it changes the environment to be more suitable to another species.

Question 33

What is chronosequence

Answer 33

A transition in vegetation that occurs in space and approximates the succession that occur over time in a habitat. These can be used to understand and observe succession over a shorter time span.

Question 34

What is primary succession

Answer 34

Occurs when a new habitat is colonized. The rate of succession is slower as habitat needs to develop, and niches are formed.

Question 35

What is secondary succession

Answer 35

Occurs after a disturbance. Disturbance acts to reduce the succession stage of a community and over time succession establishes the new climax community

Question 36

What is the climax community

Answer 36

It is the end state community from succession. It should be stable and define the habitat.

Question 37

What are the recent developments in landscape ecology

Answer 37

Ecologists historically observe abiotic and biotic influences on populations over time and space. Spatial heterogeneity was ignored as it’s difficult to observe. Technological fix and statistic methods were developed

Question 38

What is scale in landscape ecology

Answer 38

Scale is one of the key themes in landscape ecology as it allows questions of population dispersal, and conservation to be addressed

Question 39

What are corridors and steppingstones in landscape ecology

Answer 39

Useful for tracking the spread of diseases. Agricultural and human pathogens are noted. We have the potential to trace the source. We can infer corridors and steppingstone in spread of diseases.

Question 40

What are bioindicators

Answer 40

They can be a biological process or community. There is a change in the abundance or activity indicates a change in an environmental parameter. An indicator species will have physiology that is responsive to the environmental variable.

Question 41

What are microbial indicators.

Answer 41

Microbes are great indicators of biological processes as they do many of them. Microbes have been used as indicator species. Biomarker molecules include diagnostic molecules for the presence of an organism such as fatty acid, DNA, and proteins

Question 42

During the infant gut microbiome, what are the early colonists

Answer 42

Early colonists are passed directly from the mother during or even before birth, and therefore may lack characteristics that would otherwise facilitate early arrival.

Question 43

During infant gut microbiome, what happens to bacteria following birth

Answer 43

Following birth, mothers supply bacterial growth factors in breast milk and continue to introduce new taxa through physical contact

Question 44

During infant gut microbiome, what happens to the maturing infant

Answer 44

The maturing infant is beginning to suppress undesirable taxa through immune response, and actively cultivate commensal taxa by providing nitrogen-rich mucus and favourable habitat in the outer mucus layer of the large intestine.

Question 45

During infant gut microbiome, what approach did they use

Answer 45

We develop a unique approach to inferring microbial trait data, which entails (1) building a phylogeny that contains the taxa from infant gut samples and 13,900 other taxa with formally described type specimens and Latin binomials, (2) using the Latin binomials to map trait data curated from literature and online repositories onto the tips of the phylogeny, and (3) inferring unknown trait values using hidden state prediction.

Question 46

During infant gut microbiome, what did trait-based patterns show

Answer 46

The trait-based patterns in our analysis suggest that succession begins with a functionally variable cohort of early arrivers, adept at proliferating rapidly within hosts, which gradually matures into a more functionally uniform cohort of taxa able to both thrive in the anoxic gut environment and disperse between anoxic patches as oxygen-tolerance spores

Question 47

During infant gut microbiome, how do early and late successional specialists differ

Answer 47

Early and late successional specialists differed significantly in their predicted trait values: late successional specialists were less tolerant of oxygen, were more capable of sporulation, and had higher temperature optima than early successional specialists.

Question 48

During infant gut microbiome, how do we see the decline of flagella

Answer 48

The initial presence and subsequent decline of taxa likely to have flagella could mean that the ability to actively disperse over short distances improves colonization rates during early succession, but that flagella are not as advantageous in the mature gut.

Question 49

During infant gut microbiome, what do we know about the sporulating ability

Answer 49

The increase over time in predicted sporulating ability may reflect the long-term advantages of being able to disperse among hosts and/or within hosts in a dormant state during stressful conditions.

Question 50

During infant gut microbiome, what do we know about correlations among traints

Answer 50

Correlations among traits are noteworthy because they may be independent indicators of a taxon’s position on the same ecological trade-off axis. On the other hand, correlations among traits may simply be artifacts of arbitrary genomic linkage, and not independent instances of evolutionary adaptation

Question 51

During infant gut microbiome, what do we know about the differences between vaginally delivered and C-section infants.

Answer 51

Notable trait-based difference between the microbiomes in C-section infants, relative to those in vaginally delivered infants, were seen but these differences were not statistically significant after account for multiple comparisons. At minimum, these results suggest that taxa encountered by infants during vaginal delivery are functionally distinct from those encountered by infant after C-section delivery in the hospital environment.

Question 52

During infant gut microbiome, what do we know about compositional variability

Answer 52

Compositional variability was higher in the first year of development, both in term s of OTUs and predicted traits, than in second or third years of development.

Question 53

During infant gut microbiome, what do we know about compositional convergence

Answer 53

Compositional convergence across infants over development may reflect a process whereby stochastic cohort of initial taxa colonize infant guts but are gradually replaced, or supplemented with, taxa better suited for the gut environment.

Question 54

During infant gut microbiome, what does compositional differences across microbiomes tell us

Answer 54

First, it is another reminder that microbial communities with different OTU-based compositions do not necessarily differ in their functional potentials. Second, it means that community succession can be more predictable with respect to traits than OTUs.

Question 55

During infant gut microbiome, why is functional redundancy important

Answer 55

Functional redundancy among gut microbiome taxa may benefit the host by improving community resilience in response to disturbance.

Question 56

During infant gut microbiome, why are trait-based approaches important

Answer 56

Trait-based approaches, which link organismal structures to ecological functions, are poised to advance our mechanistic understanding of the gut microbiome, and their usefulness will only increase as we improve our knowledge of how traits mediate microbial interactions and as we increase the depth and breadth of microbial trait databases.