Dictyostelium can utilize one of three survival strategies when food starvation-

(1) Microcyst formation, favoured in dark & wet conditions, or ammonia levels are high.
(2) Zygote formation, favoured in dark & wet conditions, & triggered by ethylene produced by the cells.
(3) Cell aggregation & differentiation

TLS Online TPP Program

#Id: 1826

#Unit 10. Ecological Principles

dN/dt has its maximum at an intermediate population Size specifically, at N = K/2.

Maximum sustainable yield = rK/2

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#Id: 1960

#Unit 10. Ecological Principles

Quadrats- A square frame often, but not always, measuring 50 × 50 cm.

TLS Online TPP Program

#Id: 1961

#Unit 10. Ecological Principles

A cohort is a group of same-aged young which grow and survive at similar rates.

A population is often made up of organisms from a variety of different cohorts.

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#Id: 1962

#Unit 10. Ecological Principles

A life table provides data on the number of individuals alive in different age classes and the age-specific survival or mortality rates in these age classes.

TLS Online TPP Program

#Id: 1963

#Unit 10. Ecological Principles

The cohort life table follows a cohort of individuals from birth to death. 

Cohort life tables can be used to estimate the age-specific probabilities of survival.

TLS Online TPP Program

#Id: 1964

#Unit 10. Ecological Principles

A static life table accomplishes the same goal, but instead of following a cohort of individuals from life to death, data is gathered on the age structure of a given population at one point in time.