Which observation MOST directly challenges the idea of a universally applicable “molecular clock” for dating evolutionary divergence?
Fossil evidence sometimes contradicts molecular clock estimates.
Mutation rates can be influenced by environmental factors.
Different genes evolve at different rates, even within the same lineage.
Horizontal gene transfer can introduce new genes into a lineage.
Related Questions
Following are the two statements regarding the origin of life:
(i) The earliest organisms that appeared on the earth were non – green and presumably anaerobes.
(ii) The first autotrophic organisms were the chemoautotrophs that never released oxygen.
Of the above statements which one of the following options is correct?
Both (i) and (ii) are correct
(i) is correct but (ii) is false
(ii) is correct, but (i) is false
Both (i) and (ii) are false
A biologist is trying to infer how five closely related species of snakes are related to one another. She noticed that some of the snakes have forked tongues and others do not. Which of the following would help her to distinguish their ancestral state?
She looks among snake fossils for evidences that being forked is a characteristic of the ancestor of this group, but determines no such fossils exists
She locates a specimen of a more distantly related snake to see if it has a forked tongue
She looks at a representative mammal species to see if it has a forked tongue
She flips a coin
I. Oparin’s theory of origin of life is based on …A…
II. Chemical theory of origin of life was given by …B…
Choose the correct option for A and B to complete the statements I and II
A-biological evolution; B-Oparin
A-elemental evolution; B-Haldane
A-organic evolution; B-Oparin and Haldane
A-chemical evolution; B-Oparin and Haldane
Which compound has very important role in prebiotic evolution?
NO
Darwin proposed the theory of
Inheritance of acquired characters
Natural selection
Recapitulation
Continuity of germplasm
The first autotrophic organisms on Earth were likely:
Chemoautotrophs that did not release oxygen
Photoautotrophs that released oxygen
Chemoautotrophs that released oxygen
Photoautotrophs that did not release oxygen
England in 1850s, i.e., before industrialization set in, it was observed that there were more white-winged moths on trees than dark-winged or melanised moths.
However, in the collection carried out from the same area, but after industrialization, i.e., in 1920, there more dark-winged moths in the same area, i.e., the proportion was reversed
Predict the possible reason for such change
Natural selection
Artificial selection
Conditional selection
Divergent selection
Evolutionary biology is
The study of history of life forms on earth
Study of pedigrees of life forms on earth
Equivalent to demography
Equivalent to anthropology
Which of these provides evidence for evolution?
The amount of sunlight received by a location
The temperature of the Earth's core
The fossil record
The chemical composition of rocks
What does the study of biogeography contribute to our understanding of evolution?
It explains the precise mechanisms of genetic mutations.
It proves that acquired characteristics are inherited.
It demonstrates the spontaneous generation of life.
It shows how the distribution of organisms reflects evolutionary history and geological events.
