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Def:
Dispersal is the phenomenon of transferring of plant parts to distant place. Dispersal of fruits and seeds are common in angiosperms. It has great importance in their life process.
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1. If all the fruits and seeds fall under the parent plant, ail may not be able to germinate to develop seedling.
2. Seedlings will not get sufficient light and air for normal living.
3. Soil nutrition will be insufficient for them as these have been mostly used up by the parent plant, and there will be sharing of the existing nutrition present in the soil.
4. A group of same type of seedling will be developed under the parent plant.
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1.Dispersal by Wind
Some fruits rind seeds are so small and light that they may be easily carried by wind. Many of them develop crowns of hairy outgrowths and winged expansions often acting like parachutes, which help them in distribution. Hairy outgrowths are present on the seeds of cotton, Calotropis (B. Akanda), Nerium (B. Karabi).

2. Dispersal by Animals:
Many fruits and seeds are provided with spiny projections or sticky glands to adhere to the animal bodies, and are thus scattered. Andropogon (B. Chore Kanta), Achyranthes (B. Apang) have stiff hairs on the pericarp; curved hooks and barbs are present in Martynia,Xanthium (B. Okra), Plumbago (B. Chita) have glands by which they stick to the animal bodies.
Fleshy fruits like tomato, figs, develop beautiful colours to attract animals like birds, squirrels and bats. The small seeds are carried by those animals from place to place. Some of the fruits are eaten up by animals and seeds remain uninjured even when they pass through their alimentary canals. The excreta of the animals rather forms a more congenial soil for the germination of the seeds.

Even human beings are instrumental in the dispersal of many seeds and fruits of economic interest and ornamental value. Plants like water hyacinth, papaw, pine-apple which grow abundantly all over India today have come from foreign countries through human agency.

3 .Dispersal by Explosive Mechanism:
Certain fruits burst with a bit of force to scatter the seeds away from the mother plant. Familiar examples are Balsam (B. Dopati), Oxalis (B. Amrul), castor. Fruits of Rvellia (B. Chatpati), Andrographis (B. Kalomegh), burst suddenly when they come into contact with moisture. Legumes of Clitoria (B. Aparajita), dehisce by both the sutures and the two halves twist just to scatter the seeds.

4.Dispersal by Water:
Aquatic plants and plants growing on river banks and sea-shore have fruits and seeds which are dispersed through water. They have usually fibrous tissue for floating on water surface, and protective devices so that the embryo may not be damaged.
Fruits of cocoanut, Nipa (B. Golpata) are common examples. Lotus fruits remain embedded in the spongy thalamus. The seeds of water-lily contain air-spaces in the testa for ready dispersal by water.

Charles Darwin was born in 1809 in Shrewsbury, England. His father, a doctor, had high hopes that his son would earn a medical degree at Edinburgh University in Scotland, where he enrolled at the age of sixteen. It turned out that Darwin was more interested in natural history than medicine—it was said that the sight of blood made him sick to his stomach. While he continued his studies in theology at Cambridge, it was his focus on natural history that became his passion.

In 1831, Darwin embarked on a voyage aboard a ship of the British Royal Navy, the HMS Beagle, employed as a naturalist. The main purpose of the trip was to survey the coastline of South America and chart its harbors to make better maps of the region. The work that Darwin did was just an added bonus.

Darwin spent much of the trip on land collecting samples of plants, animals, rocks, and fossils. He explored regions in Brazil, Argentina, Chile, and remote islands such as the Galápagos. He packed all of his specimens into crates and sent them back to England aboard other vessels.

Upon his return to England in 1836, Darwin’s work continued. Studies of his samples and notes from the trip led to groundbreaking scientific discoveries. Fossils he collected were shared with paleontologists and geologists, leading to advances in the understanding of the processes that shape the Earth’s surface. Darwin’s analysis of the plants and animals he gathered led him to question how species form and change over time. This work convinced him of the insight that he is most famous for—natural selection. The theory of natural selection says that individuals of a species are more likely to survive in their environment and pass on their genes to the next generation when they inherit traits from their parents that are best suited for that specific environment. In this way, such traits become more widespread in the species and can lead eventually to the development of a new species.

In 1859, Darwin published his thoughts about evolution and natural selection in On the Origin of Species. It was as popular as it was controversial. The book convinced many people that species change over time—a lot of time—suggesting that the planet was much older than what was commonly believed at the time: six thousand years.

Charles Darwin died in 1882 at the age of seventy-three. He is buried in Westminster Abbey in London, England.

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