List of top Questions asked in GATE Ecology and Evolution- 2025

Across trophic levels, energy flows from producers to primary consumers, and from primary consumers to secondary consumers. Which one of the following options best represents the percentage of energy that is transferred from producers to secondary consumers?
Certain species of ibex and weevils depend on the same food source. A study finds that the removal of ibex results in an increase in the number of weevils, but the removal of weevils does not affect the ibex. Which one of the following options best describes this interaction?
Fossils of most of the modern animal phyla first appeared over a short period of time. In which one of the following geological time periods did this occur?
Which one of the following is an example of a cell type found only in a single phylum?
A bird eats two types of worms, P and Q, picking them randomly. Which one of the following describes the kind of probability distribution of the number of worms of type P eaten by the bird in a day?
The hippocampus is a region of the brain whose size is positively correlated with navigation and spatial mapping ability in birds and mammals. Which one of the following observations would NOT be consistent with this statement?
A butterfly species in a homogenous forest patch starts exhibiting assortative mating, such that spotted individuals always mate with each other and plain individuals always mate with each other. This trait is heritable, and spotted parents always produce spotted offspring and plain parents always produce plain offspring. Which one of the following forms of speciation could this prezygotic reproductive barrier most likely lead to?
Lizards that produce many eggs often have a shorter lifespan than those who produce fewer eggs. Which one of the terms below describes the relationship between the number of eggs and lifespan?
Male rhinoceros beetles have horns that they use to fight each other. Despite the competitive advantage of having large horns, horn length never exceeds two thirds of their body length. What form of selection explains why horn length is constrained?
Hosts of parasites evolve effective immune responses to infection, which in turn results in those parasites evolving increased infectiousness towards the hosts. Which one of the following processes describes this type of interaction between hosts and parasites?

In primates, males are often larger than females. If sexual dimorphism evolved to enable males to compete for access to multiple females, in which mating system would we expect to see the greatest sexual dimorphism?

Fly larvae of a species feed simultaneously on a shared rotting fruit. If the density of fly larvae is high, then all the larvae grow up to be smaller sized adults than if the larval density were low. Which one of the following processes best describes this observation?
In a linear regression, a line of best fit can be obtained by
There are 9 different rock lizard species, each with a unique colour. Lizards of 2 different species sit on a rock at any given time. The number of possible colour combinations of rock lizards seen together on a rock is:
Rotting leaves of mango are composed of 25% of compound P which decomposes exponentially at a rate \( k_P = 0.5 \, {yr}^{-1} \) and 75% of compound Q which decomposes exponentially at a rate \( k_Q = 0.1 \, {yr}^{-1} \). What percentage of the initial amount of compound Q remains when half of the initial amount of compound P has decomposed? Choose the closest numerical value from the options provided.