Pax-6 usually causes the production of a type of light-receptor pigments. In vertebrate eyes, though, a different gene (the rh gene family) is responsible for the light-receptor pigments of the retina. The rh gene, like Pax-6, is ancient. In the marine ragworm, for example, the rh gene causes production of c-opsin, which helps regulate the wormʹs biological clock. Which of these most likely accounts for vertebrate vision?

#Question id: 10234

#Unit 10. Ecological Principles

You observed the two species of barnacles, species 1 and species 2, occupy upper and lower strata of intertidal rocks, respectively. Only when species 1 was removed by you from the upper strata, species 2 could occupy both the upper and lower strata. From the choice given below what would be your inference from these observations.

#Question id: 10235

#Unit 10. Ecological Principles

Following some observation is correct about species of P, Q and R

A) Species P and R have generalized nich while Q has specialized nich

B) Species P and R have specialized nich while Q has generalized nich

C) Species P and R are more prone to extinct than Q species

D) Species Q is more prone to extinct than either P or R species

#Question id: 10236

#Unit 10. Ecological Principles

Following figure represent fundamental and realized nich of species P and Q in gradient of temperature along sea shore. which of the following statement are correct? 

A) Fundamental niche of species P is greater than its realized nich

 B) Fundamental niche of species Q is greater than its realized nich

 C) Species Q is strong competitor than species P

 D) There is no effect on spaced occupied by Q in the presence or absence of species P

#Question id: 10237

#Unit 10. Ecological Principles

Which of the following is the most logical conclusion about the distribution of the two species of barnacle, Chthamalus and Balanus?

#Question id: 10238

#Unit 10. Ecological Principles

The diagram below shows the frequency distribution of two closely related bird species based on their resource use in sympatric. Which one of the following phenomena most appropriately explains the change in frequency distributions of species 1 and 2 in the figure given above?

#Question id: 10241

#Unit 10. Ecological Principles

In an Asian rice paddy, carp eat decaying material from around the base of rice plants while a snail scrapes algae from the leaves, stems, and roots of the same plant. They can survive at the same time in the same rice paddy because they