Question

So, Grime’s stress-disturbance classification vs. Winemiller & Rose’s opportunistic-equilibrium-periodic classification. Things to know: variables associated with each. Types of organisms that best fit each one (plants? Animals? Others?). Why are such classifications useful? What can we learn from them (example topics: conservation, invasive species, succession). I’m pretty much giving you the one possible question, so I’ll be expecting some depth here. Study well!

Answer 1

Winemiller & Rose’s opportunistic-equilibrium-periodic classification

Opportunistic species are classified based on the factors like low juvenile survival, a low number of offsprings and early maturity. Equilibrium species are classified based on the high juvenile survival, low numbers of offsprings and late reproductive maturity. The periodic strategy involves low juvenile survival, the high number of offsprings and late maturity. Life histories that lie on the triangular surface with three endpoints called opportunistic, equilibrium and periodic. According to this classification, mammals show the least variation in the life history strategies.

The variables associated with this classification type are survival, number of offsprings and age at reproductive maturity. Animals fit this type of classification better.

Benefits of this classification

Life history classification of animal species based on three type of life histories, opportunistic, equilibrium and periodic.

By plotting the variation among vertebrates based on their life histories on an axis using certain variables, the amount of life history variation can be understood and observed among the groups. Example: Fish show great variation while mammals show the least. Intermediate variation is observed by birds, reptiles and amphibians.

The relationship between adult survival and reproductive allocation is established.

The trade-off between offspring number and size is put by the constraints due to energy use.

Grime’s stress-disturbance classification

High and low-stress intensities and disturbances are the main factors in classifying the plants as competitors, stress-tolerators and ruderals. Stress tolerance is mainly dealt with mineral nutrition stress.

Some of the variables associated with this classification type are environmental variables such as temperature and drought. Mineral nutrition is another variable. Plants fit this type of classification better. Ruderals are the plants that are found to be dominant under high disturbance and low-stress conditions. No plant can survive under high stress and high disturbance. Plants dominant under low disturbance and high stress are stress tolerant ones.

Benefits of this classification

The study of the relationship between the timing of ecological events and climate is done here.

For example, winter migratory patterns and timing of flower blooms.

Study of plants and classifying them as rapidly growing, short lifespan, semelparity and dormancy. Some plants classified as herbivores with poor resource conditions and growing very slowly.