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(d) sedimentary rocks

Natural selection: Heritable variations that enable survival of the fittest will leave greater number of progeny. Natural selection can have following three effects: 

a. Stabilisation: Larger number of individuals acquire mean character value so peak gets higher and narrower. 

b. Directional change: Large number of individuals acquire value other than mean character value so peak shifts in one direction. 

c. Disruption: Large number of individuals acquire peripheral character values at both ends of the distribution curve and hence 2 peaks are formed.

(b) Weismann

Peripatus is a worm that shown the characters of both Annelidia and Arthropoda. Hence it is a connecting link between Annelida and Arthropoda.

Archaeopteryx – connecting link between Reptiles and Aves. 

Peripatus – Connecting link between Annelida and Arthropoda.

Fossils are remains of hard parts (like bones, teeth, etc.) of life-forms found in rocks.

Correct option (b) Lichens

Explanation:

Lichens are sensitive to SO₂ pollution. Lichens are very good pollution indicators, they do not grow in polluted areas.

Divergent & Convergent Evolution

What is Evolution?
Our earth is accomplished with numerous life, which may be within the sort of a microorganism or big sort of a whale. It is believed that each one sort of life present on earth to date have developed from one living cell, which further gave rise to other sorts of life; this process is named evolution.

Theory of Evolution doesn't tell us exactly how life began on earth -but it helps us understand how life -once it came into existence -diversified into the various incredible forms we see now an within the fossil record. It also helps us make sense of how modern creatures continue to adapt and change today. 

In biology, it also helps us add up the way during which modern organisms still adapt and alter currently
.
In biology, evolution is often defined as any change in the heritable traits (those are physical traits like fur colour mice, spots on the wings of butterflies, or
instinctive behaviours just like the way during which dogs greet their friends with a sniff) within a population across generations.

Definition Of Convergent Evolution
The development of a similar adaptive functional structure in unrelated groups of organisms is called convergent evolution. Analogous organ shows convergent evolution. Organisms in unrelated groups show a similar adaptation by evolving similarly. They provide evidence through analogous organs. Presently, cats and octopus are very much different from each other but still both of them adaptive similar way just to see things.

Examples of Convergent Evolution

1.Eye of octopus and eye of a cat.
First of all, just see the groups of both the species octopus and cat both are from the unrelated groups; the eyes of both are structurally different. Still, their eyes are performing the same function, so the eye of the octopus and eye of the cat provides evidence of convergent evolution.

2. Stings of honey bee and scorpions.

3.The fin of fishes and flipper of whales.
Structurally they do not belong to the same origin, they have a huge difference, but when you look at their purpose, the fin of fishes and flipper of whales have the same purpose, i.e. they help in water to swim.

Definition of divergent evolution.
The development of different functional structures from a common ancestral form is called divergent evolution. Homogeneous organs show divergent evolution. Accumulation of differences between groups leads to the formation of new species. Homologous organs show divergent evolution—homologous means the same structures from the same origins, but different functions. So here we are not talking about an unrelated group of organisms. We are talking about a related group of organisms because the only related group of organisms have the same structures,  so they have a similar structure, but over a long time, they perform different functions.

Examples of Divergent Evolution
1. Mouth part of cockroach, honey bee, and butterfly.
Structurally the mouth face of honey bee butterfly and cockroach are the same but looking at the food habits of these are very different from each other. Cockroach they just need very small. But as you see the honey bee they sucked the bigger part from the flower.o their food habits are different, but the structure is the same.
2. Thorn in bougainvillaea and tendrils in Cucurbita
3. Limbs of lizards frog bats horses and humans.

Comparison Between Convergent and Divergent Evolution

1. Definition
 
Convergent Evolution: When one or more different species evolve similarities in their characteristics and functions because of adaptations in an environment.
Divergent Evolution: When an ancestral species diverges into multiple different species, ultimately giving rise to new species.

2. Origin of evolution

Convergent evolution: They evolve from different species but develops similar characteristics, like wings of birds and insects.
Divergent Evolution: They evolve from the same species and gradually give rise to new species like Darwin finches which have evolved in around 80 new species.

3. Way of living

Convergent evolution: They live closely in the same way as other species, of which it has adopted the changes.
Divergent Evolution: They live in different ways from their ancestor.

4. Appearance

Convergent evolution: The outer structure of a species may be different, but internally they resemble their ancestors.
Divergent Evolution: As this type give rise to totally new species, they can be different from outside as well as inside in appearance.

5. Type of structure

Convergent evolution: Organisms evolve Analogous structure despite evolving from different ancestors.
Divergent Evolution: These kind have a Homologous structure (means structure are same, but functions are different), despite appearing similar to ancestors.

6. Evolution Cause

Convergent evolution: It is due to a change in environmental conditions, or due to the place where they are living.
Divergent Evolution: Due to migration or may be due to environmental changes

Difference Between Convergent and Divergent Evolution

When two or more different species developed similar characteristics thanks to the adaptation to the actual environment, but they are doing not belong to the same ancestor are kept under Convergent Evolution. In convergent evolution, two or more distinct species share traits not due to a common ancestor so let's take birds bats and butterflies, for example, all of them have wings that allow them to fly. Still, they don't share a common ancestor with wings, so each one evolved to have wings independently right evolution converged on a similar trait in different species. Hence, their wings are not due to their to a common ancestor all.

While divergent evolution is the phenomenon of two species having common ancestors, but they develop different characteristics thanks to changes within the environment which they adapt slowly and hence give rise to new species. In divergent evolution, two or more distinct species share a common ancestor from which they both diverged. A common example is an elephant and the woolly mammoth; they both share a common ancestor and yet evolved into two different species. Another example is the dog the wolf and the fox, again they share a common ancestor yet evolved independently.

This information promises to revolutionise the processes of finding chromosomal locations for disease-associated sequences and tracing human history.

It help lo find chromosomal locations for disease - associated sequences, and tracing human history.

Chromosome 1 has most genes (2968) and the Y chromosome has fewest genes (231).

Chromosome 1, Y