Darwin proposed his theory of natural selection on the basis of
Mutation
Environmental factors
Lama's theory
Chromosomal aberrations
Correct Answer :
B. Environmental factors
Related Questions
Connecting link between nonchordata and chordata is
Peripatus
Archaeopteryx
Tachyglossus
Balanoglossus
Co-worker of Darwin was
Bateson
Mendel
Wallace
Lamarck
Appearance of ancestral characters in the new born, such as tail, monstral face, gill slits, multiple mammale etc. are known as
homologous
analagous
ativistic
vestigeal
The diploid number of chromosome in Chimpanzee, Gorilla and Orangutan is
2n = 44
2n = 46
2n = 48
none of these
Amphibians appeared and became dominant in the
Mesozoic era
Coenozoic era
Palaeozoic era
None of these
The fossil formed from harder parts of the body infiltrated by minerals and turned into stony shapes is
moulds
coprolites
petrified
cast
The function affected by point mutation in p-globin in sickle cell anaemia is
protein folding
transcriptional control
nonsense mutation
none of these
In forming the theory of evolution by Natural Selection, Charles Darwin was greatly influenced by
environmental factors
mutations
malthu's ideas on population control
all of these
We use the term hybrid breakdown when the
offspring of hybrids are inviable or sterile
a hybrid zygote is formed but it fails to develop
hybrid adults fail to produce functional gametes
sperms and ova of different species of animals are unable to fuse
Human beings living in different geographical areas and under different environmental conditions are kept under one species because
they show adaptive variations to their environment
they share the common karyotype
they can freely interbreed and share a common gene pool
their features are different yet they are similar essentially
Along with reduction in the number of toes in the modern horse, the other most significant evolutionary change is
increase in the size of eyes
increase in the size of brain
straightening of back
change in dentition from browsing to grazing
The idea of "Survival of fittest" was given by
Darwin
Herbert Spencer
Mai thus
Lovell
A connecting link between Annelids and Arthropods is
Peripatus
Palaemon
Limulus
Heteronereis
The book "Voyage of the Beagle" is concerned with which one of the following ?
Lamarckism
Theory of natural selection
Bird flight mechanisms
Both and
An animal is more likely to be preserved as a fossil if it contains large quantities of
cartilage and bone
proteins
inorganic materials
keratin materials
An example of analogy is
wings of a bird and butterfly
wings of pigeon and bat
limbs of horse and man
paddles of dolphin and fins of a fish
Which were dominant during Mesozoic era
Pisces
Birds
Ruling mammals
Ruling reptiles
The first life on earth came in water and evidences indicate that life originated in one of the following eras :
Paleozoic
Mesozoic
Cenozic
Proterzoic
A fossil is a
laboratory preserved animal
dead animal of the past
organic relic of the past
stuffed animal
A kind of mimicry which presumably works as a double insurance is
batesian mimicry
mullerian mimicry
warning colouration
concealing colouration
Which of the following gases were absent in free form when life originated on earth?
Oxygen
Hydrogen
Methane
Ammonia
A starfish with six arms, may be a case of
variation
evolution
autotomy
mutation
The study of Galapagos Finches shows
adaptive radiation
adaptive convergence
use and disuse of organs
none of these
Role of isolation in evolution is
differentiation of species
maintenance of species
evolutionary divergence
extermination of species
Survival due to geographic isolation is best exemplified by mammalian fauna of
Oriental region
Ethiopian region
Australian region
Palaearctic region
The epoch of human civilisation is
Pliocene
Holocene
Pleistocene
Palaeocene
Doubis in 1891 found the fossil of Java ape man. It is
Sinanthropus pekinensis
Homoerectus
Homo rhodesiensis
Homo spisaens
The first mammal arose
after the extinction of dinosaurs
before the origin of dinosaurs
along with dinosaurs
from the dinosaurs
The resemblance between the south American llama and the African camel indicates a common ancestry. This is
homological evidence for evolution
palaentological evidence for evolution
biogeographic evidence for evolution
none of these
Fire was first used for protection and cooking by
Java man
Neanderthal man
Peking man
Cromagnon man