The repeated evolution of a specific trait or body plan from the same ancestor lineage but at different times is termed as (1) Iterative evolution (2) Convergent evolution (3) Coevolution […]
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CSIR NET Life Science Previous Year Questions and Solution on Emergence of Evolutionary Thoughts
Cuvier’s Theory of Catastrophism: How Catastrophic Events Shaped Life on Earth
The Cuvier’s theory, which states that there had been several creations, each preceded by another due to some large scale geographical disturbances. Such theory is termed as- (1) Theory of […]
CSIR NET Life Science Previous Year Questions and Solution on Emergence of Evolutionary Thoughts
Why Gill Clefts Rarely Appear in Higher Animals: The Evolutionary Return of Ancestral Traits
Rarely there is occurrence of gill clefts in higher animals. The reason for this rare appearance is (1) They may be useful for that organism (2) Ancestral returns of that […]
CSIR NET Life Science Previous Year Questions and Solution on EVOLUTION AND BEHAVIOUR
Horizontal Gene Transfer: The Key to Conflicting Phylogenetic Trees in the Tree of Life
When James R Brown and W Ford Doolittle (1997) reconstructed the tree of life using a variety of different genes, they found that different genes gave fundamentally different phylogenies as […]
CSIR NET Life Science Previous Year Questions and Solution on EVOLUTION AND BEHAVIOUR
Decoding the Evolutionary Relationships Among Bacteria, Archaea, and Eukarya: Insights from Phylogenetic Trees
In the phylogenetic tree above, branch-lengths are drawn proportional to the number of changes along a lineage. The following inferences were made from this tree. (A) Bacteria are more closely […]
CSIR NET Life Science Previous Year Questions and Solution on Emergence of Evolutionary Thoughts
Early Embryonic Similarities Between Pig and Mouse: Evidence for Common Ancestry
Early embryonic stages of pig and mouse are almost identical, it reveals- (1) Common ancestry (2) Progressive evolution (3) Directional Evolution (4) Homoplasy Introduction The early stages of embryonic development […]
CSIR NET Life Science Previous Year Questions and Solution on Emergence of Evolutionary Thoughts
Stable Cell Wall-Deficient Bacteria and the Proof of Adaptive Mutation: Understanding Bacterial Evolution
In an experiment bacterial cell wall was removed usingenzymatic methods. It was observed that on culturingsuch cell wall deficient bacteria, for many generations result into stable forms of bacteria permanently lacking cell […]
CSIR NET Life Science Previous Year Questions and Solution on EVOLUTION AND BEHAVIOUR
Parsimony and the Evolution of Male Body Color in Species: Decoding Ancestral States
The phylogenetic tree below shows evolutionary relationships among 8 species. Males of these species are either blue (b) or red (r) in colour, the colour being indicated next to each […]
CSIR NET Life Science Previous Year Questions and Solution on Emergence of Evolutionary Thoughts
When Were the First Fossils Discovered? A Look at Fossil History Before Lamarck and Darwin
First fossils were discovered (1) Prior to both Lamarck and Darwin (2) Prior to Lamarck but after Darwin (3) After Lamarck but prior to Darwin (4) After Lamarck and Darwin […]
CSIR NET Life Science Previous Year Questions and Solution on EVOLUTION AND BEHAVIOUR
Using Parsimony to Infer Ancestral Plumage Color in Birds: Red or Blue at the Root?
The phylogeny below shows evolutionary relationships between 9 extant bird species and whether they display red or blue plumage. Based on the above phylogeny and the distribution of red and […]
