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Inspite of interspecific competition in nature, which mechanism the competing species might have evolved for their survival? 
While they do not rule out the occurrence of interspecific competition in nature, they point out that species facing competition might evolve mechanisms that promote co-existence rather than exclusion. One such mechanism is ‘resource partitioning'.
Which of the following is not an attribute of a population? 
Species interaction refers to direct and indirect interrelationship between different organisms, while on the other hand population attributes include population size, population density, population spacing, and age structure. Mortality is the ratio of deaths in an area to the population of that area; expressed per 1000 per year. Sex ratio is the ratio of males to females in a population.
Carnivorous animals lions and leopards, occupy the same niche but lions predate mostly larger animals and leopards take smaller ones. This mechanism of competition is referred to as 
Natality refers to 
Natality refers to the number of births during a given period in the population that are added to the initial density. Death rate or mortality is the number of deaths in the population during a given time period. Immigration is the number of individuals entering a habitat. Emigration is the number of individuals of the population that left the habitat and had gone elsewhere during a time period.
Asymptote in a logistic growth curve is obtained when 
Asymptote in a logistic growth curve is obtained when population density (N) reaches the carrying capacity (K), i.e., N = K.
When does the growth rate of a population following the logistic model equal zero? 
The logistic model is given as dN/dt = rN(1–N/K)
Logistic growth of a population size occurs when resources are limited. The formula we use to calculate logistic growth adds the carrying capacity as a moderating force in the growth rate.
► The logistic model is given as dN/dt = rN(1-N/K)
When the value of N/K is one, then,
► dN/dt = rN(1-N/K)
► dN/dt = rN(1-1)
► dN/dt = rN(0)
► dN/dt = 0 (zero)
So, the growth rate of the population will be equal to zero.
Gause's principle of competitive exclusion states that: 
Gause's principle of competitive exclusion can be restated to say that no two species can occupy the same niche indefinitely when resources are limiting.
Gause's theory predicts that when two species coexist on a long-term basis, either resources must not be limited or their niches will always differ in one or more features; otherwise, one species will outcompete the other and the extinction of the second species will inevitably result, a process referred to as competitive exclusion.
In which of the following interactions both partners are adversely affected? [2015 RS]
Competition occurs for light, food and space among organisms in which all partners are adversely affected in an ecosystom.
Most animals that live in deep oceanic waters are: [2015 RS]
Most animals that live in deep oceanic waters and called benthos are scavengers or detritivores i.e. organisms that feed on dead plants and animal residues.
A population will not exist in Hardy - Weinberg equilibrium if: [2015 RS]
Most animals are tree-dwellers in a: [2015 RS]
In tropical rain forest zone, most of the animals prefer to live on trees. The reason is that the floor of forest is full of humidity, decomposing leaves and other organic matters and is the habitat of insects etc.
If 20 J of energy is trapped at the producer level, then how much energy will be available to peacock as food in the following chain? 
Plant → Mice → Snake → Peacock
The zone of atmosphere in which the ozone layer is present is called: 
The ozone (O3 ) found in upper part of the atmosphere, i.e., Stratosphere, is Good ozone, since, it acts as a shield for absorbing UV-radiations from sun.
Just as a person moving from Delhi to Shimla to escape the heat for the duration of hot summer, thousands of migratory birds from Siberia and other extremely cold northern regions move to: 
Given below is a simplified model of phosphorus cycling in a terrestrial ecosystem with four blanks (A-D). Identify the blanks: 
Phosphorus is a major constituent of the biological membrane, nucleic acids, and cellular energy transfer system.