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:

Define/Explain: Ecotype.

Provide information about the natural habitats of organisms.

Which of the following levels is not considered a biological level of organization in terms of size?

Consider the following four conditions $(i-iv)$ and select the pair that represents the adaptation of desert lizards to their environment.
$(i)$ Burrowing into the soil to escape high temperatures.
$(ii)$ Rapidly losing body heat during high temperatures.
$(iii)$ Basking in the sun and absorbing heat when the temperature is low.
$(iv)$ Insulating the body due to a thick layer of fat.

Which of the following hierarchies is correct with reference to the levels of biological organization?