Free IAS coaching day 52

Adaptation/Interaction between Species

Adaptation Interaction between Species


An adaptation is “the appearance or behaviour or structure or mode of life of an organism that allows it to survive in a particular environment”.
Some adaptations are structural. Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Examples of Adaptations
a) Webbed feet
In most aquatic animals, swimming is a must. To aid swimming, many animals have adapted and evolved with webbed feet. Webbed feet help animals propel themselves through the water with ease. This can help the animal swim faster to catch prey or escape a predator. Also, if an animal has to swim long distances, webbed feet can help it save energy so it can swim farther
b) Sharp Claws
Sharp claws can be used for many different purposes. For instance, many herbivores use their sharp claws for digging for berries, roots, and herbs or burrowing for shelter. Animals that eat meat may use their claws for killing their prey or tearing meat from their kills. Also, claws can be used to increase traction to run faster, as in the case of the cheetah. Other times, sharp claws have evolved for use in defense.
c) Sharp Teeth
Sharp teeth help an animal eat meat. Found primarily on meat-eating animals, or carnivores, sharp teeth are used mainly for the tearing and chewing of an animal’s prey. Rather than developing the dull teeth of plant-eaters, or herbivores, carnivores rely on their sharp teeth to allow them to eat and survive. Sharp teeth can serve another purpose: defense.
d) Large beaks
The large beak of the macaw has been adapted to help it crack open large nuts to reach the sweet fruit and pulp inside. On other birds however, the large beak is used to tear meat, as in the case of the rhinoceros hornbill. The rhinoceros hornbill uses its large beak to tear meat off of an animal it scavenges — usually the result of another animal’s kill.
e) Striped Fur
Striped fur is one variation of a special adaptation called camouflage. Striped fur, in most cases, helps animals blend into their environment. This helps the animal in one of several ways, including hiding from predators and sneaking up on prey. Striped fur, as in the case of a tiger’s vertical stripes, serves the animal by helping it match the surrounding vegetation, thus making it nearly invisible to other animals.
f) Brightly Colored Feathers
Brightly colored feathers can serve several purposes, including camouflage, defense, and mating. In some parts of the rain forest, the macaw and its brightly colored feathers can hide amid similarly brightly colored plants and flowers. The male peacock uses its bright feathers for another purpose: attracting a mate.
Other examples:
a) Desert animals prevent water loss from their body by reducing surface area, making skin impermeable through its thickening and hardening, as well as through the presence of scales and spines (Phrynosoma, Moloch), reducing the number of sweat glands in mammals, avoiding day heat by seeking the shadows of rocks and becoming active at night (nocturnal), and excreting wastes as solid dry pellets.
b) Some desert animals store water in their body and use it economically; the camel stores water in the tissues all over the body, whereas the desert lizard (Uromastix) stores it in the large intestine.
c) Mimicry is defined as the imitation of one organism by another for the purpose of concealment, protection, or other advantages. The species that imitates is called a mimic and the one which is copied a model. Depending on the purposes of mimicry, it can be protective or aggressive.
d) In Tundra climate most of the plants are small, grow close together and close to the ground. This protects them from the cold temperatures and the strong winds. The animals in these regions are usually white or light colored, e.g., polar bear, penguin. This adaptation helps them in maintaining their body temperature, and in camouflaging. These animals can store fat in their body as they eat a lot during the summer. In hibernation, their metabolic activity is reduced to a great extent. In this state, their heartbeat, breathing rate and temperature become very low.

Early Vedic Age/Later Vedic Age/ Vedic Literature

Vedic Age Later Vedic Period/ Painted Grey Ware Phase (1000-600 B.C.) Vedic Literature

Early Vedic Age: Ancient History

• The Vedic civilization is named after the Vedas, especially the Rig Veda, which is the earliest specimen of the Indo-European language and the chief source of information on the history of this period.
• The Vedic Civilization flourished along the river Saraswati, in a region that now consists of the modern Indian states of Haryana and Punjab.
• Later, they moved into Indo-Gangetic plains.
• They were mainly a cattle-keeping people, and were mainly in search of pastures.
• By 6th century B.C., they occupied the whole of North India, which was referred to as Aryavarta.
• This period between 1500 B.C and 600 B.C is divided into the Early Vedic Period or Rig Vedic Period (1500 B.C -1000 B.C) and the Later Vedic Period (1000B.C – 600 B.C).
• Many historians have given various theories regarding the original place of the Aryans, however, largely accepted view is the Central Asian Theory given by Max Muller.
• It states that the Aryans were semi-nomadic pastoral people around the Caspian Sea in Central Asia.
• The holy book of Iran ‘Zend Avesta’ indicates entry of Aryans to India via Iran.
• A section of Aryans reached the frontiers of the Indian subcontinent around 1500 BC and first settled in Punjab and it is here, in this land, where the hymns of Rigveda were composed.
• The Aryans lived in tribes and spoke Sanskrit, which belonged to the Indo-European group of languages.
Area of Settlement
• The geographical area covered by the early Aryans is indicated from certain allusions in the Rigveda, which seems to have been limited to an area extending from Afghanistan to the Gangetic valley.
• The former region was occupied by the Aryans is from the mention of rivers like the Kubha (Kabul), the Suvastu, situated north of Kabul.
• The Sindhu , identical with the Indus, is the river par excellence of the Rigvedic Aryans and is repeatedly mentioned, so also are its five tributaries – the Vitasta (Jhelum), Asikni (Chenab), Parushni (Ravi), Vipasa (Beas) and the Sutudri (Sutlej).
• Similarly, Dirsadvati (Chantang) is named, but the Sarasvati, now lost in the sands of Rajasthan, was first of the Rigvedic river as its banks witnessed the development of Vedic rituals and cult of sacrifices.
• The Yamuna is twice mentioned and the Ganga only once.
• They knew the Himalayas as one of its peak ‘Mujavat’ – a source of some plant and probably in Kashmir, is directly mentioned.
• They knew nothing about the Vindhyas and were not familiar with the sea.
Political Organisation
• The basic unit of political organization was kula or family and Kulapa was the head of the family.
• Several families joined together on the basis of their kinship to form a village or grama.
• Villages were headed by Gramini who used to represent village in Sabha and Samiti.
• A group of villages constituted a larger unit called Visu. It was headed by Vishayapati.
• The highest political unit was called jana or tribe.
• There were several tribal kingdoms during the Rig Vedic period such as Bharatas, Matsyas, Yadus and Purus.
• The head of the kingdom was called as Rajan or king. He was the leader in battle and protector of tribe.
• The Rig Vedic polity was normally monarchical and the succession was hereditary.
• However, the Rajan was a kind of chief, and he did not exercise unlimited power, for he had to reckon administration with the tribal councils like Sabha, Samiti, Gana and Vidhata.
• There were two popular bodies (tribal organizations) called the Sabha and Samiti. The former was a council of elders and the latter, a general assembly of the entire people.
• Even women attended Sabha and Vidhata.
• The king was assisted by a number of officers of which Purohita was the most important.
• The Rigveda did not mention any officer for administering justice.
• Spies were employed to keep an eye on unsocial activities such as theft and burglary.
• The titles of the officials do not indicate their administration of territory. However, some officers seem to have been attached to territories. They enjoyed authority in the pasture grounds and settled villages.
• The officer of pasture ground was called ‘prajapati”, who led the heads of the families called ‘kulapas’ or the heads of the fighting horses called ‘gramanis’ to battle.
• In the beginning, the gramani was just the head of a small tribal fighting unit. But when the unit settled, the gramani became the head of the village and in course of time he became identical with Prajapati.
• The king did not maintain any regular army but in times of war he mustered a militia whose military functions were performed by different tribal groups called vratas, grama, gaha, sradha, etc.
• By and large, the military system was strong. The military technique of the early Aryans was much advanced. The Aryans succeeded everywhere because they possessed chariots driven by horses.
• There was no regular revenue system and the kingdom was maintained by the voluntary tribute (Bali) of his subjects and the booty won in battle.
Social Life
• The Rig Vedic society was patriarchal.
• The basic unit of society was family or graham. The head of the family was known as grahapathi.
• Marriage was usually monogamous and indissoluble, but there are few instances of polyandry, levirate and widow-marriage.
• Polygamy was prevalent among the royal and noble families. There was no child marriage and the practice of sati was absent.
• The wife took care of the household and participated in all the major ceremonies.
• Women were given equal opportunities as men for their spiritual and intellectual development.
• There were women poets like Apala, Viswavara, Ghosa and Lopamudra during the Rig Vedic period. Women could even attend the popular assemblies.
• Aryans were fond of food, dresses, soma and sura.
• Both men and women wore upper and lower garments made of cotton and wool.
• A variety of ornaments were used by both men and women.
• Wheat and barley, milk and its products like curd and ghee, vegetables and fruits were the chief articles of food.
• The staple crop was ‘yava’, which meant barley.
• Soma was drunk at sacrifices and its use was sanctified by religion. Sura was purely secular and more potent, and was diapproved by the priestly poets.
• Chariot racing, horse racing, dicing, music and dance were the favourite pastimes.
• The Aryans loved music, and played the flute, lute and harp. There are references to singing and dancing, and to dancing girls.
• People also delighted in gambling.
• As they settled among the dark aboriginals, the Aryans seem to have laid greater stress than before on purity of blood, and class divisions hardened, to exclude those dasas who had found a place in the Aryan society, and those Aryans who had intermarried with the dasas and adopted their ways.
• Gradually, the tribal society got divided into three groups warriors, priests and commoners. Later, the fourth division called dasas or shudra was also added.
• The fourth division appeared towards the end of the Rig Vedic period because it is mentioned for the first time in the tenth book of the Rig Veda.
• The term varna was used for color, the Aryans being fair and the dasas being dark.
• The social divisions were not rigid during the Rig Vedic period as it was in the Later Vedic Period.
Economic Condition
• The Aryans came to India as semi-nomadic people with a mixed pastoral and agricultural economy, in which cattle-rearing played an important role.
• Cattle formed their most valued possessions and chief form of their wealth.
• The cow was in fact a sort of currency and values were reckoned in heads of cattle. Importance of the cow can-be measured from the fact that many early linguistic expressions were associated with cattle.
• Word for battle came to be known as ‘gavishth’ , literally, a search for cows.
• Those who lived in the same cowshed came to belong to the same ‘gotra’, which later indicated a common ancestor.
• The daughter was known as ‘duhitri’, milker of the cow.
• The cow is described in one or two places in Rigveda as `aghnya’, not to be killed; but this may imply only its economic importance.
• It was not yet held sacred. This indicates that cow was the most important form of wealth.
• Whenever gifts were made to priests, it was in terms of cows and never in terms of measurement of land.
• Gavyuti was used as a measure of distance and Godhuli as a measure of time.
• Of the other animals reared by the Aryans, the horse was the most important of them.
• The horse was essential for movement, to speed in war and it drew the chariots.
• Among other domestic animals, the early Aryans knew the goat and sheep which provided wool, their chief textile.
• Of the wild animal, lion was known earlier than tiger. The elephant was look upon with curiosity.
• Since domesticated animals seem to have been tended by common herdsmen, it has been suggested that they were under the common ownership of the members of the tribe.
• With the knowledge and use of iron they were able to clean forests and bring more lands under cultivation.
• There were artisans like carpenters, weavers, cobblers, potters, etc.
• Carpentry was an important profession and the availability of wood from the forests cleared made the profession profitable. Carpenters produced chariots and ploughs.
• Workers in metal made a variety of articles with copper, bronze and iron.
• Their bronze smiths were highly skilled, and produced tools and weapons much superior to those of Harappan culture.
• Spinning was another important occupation and cotton and woolen fabrics were made. Goldsmiths were active in making ornaments.
• The potters made various kinds of vessels for domestic use.
• Trade was another important economic activity and rivers served as important means of transport. Trade was conducted on barter system.
• In the later times, gold coins called nishka, Krishnal and Satmana were used as media of exchange in large transactions.
• Possibly they lived in some kind of fortified mud settlements. At a site in Haryana (Bhagwanpura), a thirteen-room mud house has been discovered, which might have been a house for a large extended family or for a tribal chief.
Rig Vedic Mythology
• The earliest religious ideas of the Aryans were those of a primitive animism where the focus was around them, which they could not control or understand, were invested with divinity and were personified as male or female gods.
• The Vedic Aryans were primarily worshippers of nature.
• The early gods of the Aryans, like those of the Greeks, were atmospheric gods and predominantly male. There was no fixed order of seniority among the gods.
• In the traditional classification of gods, there has been a three-fold division.
(1) Terrestrial Gods in which Prithvi, Brihasapati, Agni and rivers are important.
(2) Intermediate or Madhyamsthana gods in which Indra, Prajanya and Rudra are prominent.
(3) Celestial or Dyusthana gods, among which Varuna, Usha, Surya, Savitri and Vishnu are important.
• Among these gods, Indra was the god of strength, foremost in battle, always ready to demolish dragons and demons. He has been called ‘Pirrandar’ or ‘breaker of ports.’ He is also the god of rain and thunder. Rowdy and amoral, Indra is described as fond of feasting and drinking. The largest number of hymns, 250 in number, were addressed to Indra.
• To Agni, 200 vedic hyms were addressed. He dominated the domestic hearth and marriages were solemnised in the presence of fire. Fire was the purest of the five elements and was held in particular esteem. Fire also acted as a kind of intermediary between the gods on the one hand and the people on the other. The oblations offered to Agni were supposed to be carried in the form of smoke to the sky and thus transmitted to the gods.
• Varuna, the upholder of cosmic order, personified waters. Whatever happened in this world was thought to be the reflection of his desires. Of all the Aryan gods, Varuna was ethically the highest. Varuna was so pure and holy that performances of sacrifice would ensure his disfavour. He abhorred sin or that which was not conformable to ‘rita.’
• Surya (sun), Savitri (god to whom the famous gayatri mantra is addressed) and Pushan (guardian of roads, herdsmen and straying cattle) were the principal solar deities.
• Sonra was originally a plant from which a patent drink was produced which was consumed only at sacrifices and which caused the most invigorating effects. The god Sonia was identified with this intoxicating juice.
• Yama was the god of death and held a prominent place.
• Rudra was a remote god, dwelling in mountains and generally an object of fear. But he was the guardian of healing herbs.
• Tvastri was the Vedic vulcan god.
• Aryanyani was the guardian of forests and Vayu, the wind-god.
• Besides this, the cosmos, was also personified by large variety of celestial beings.
• Some female gods like Ushas and Aditi are also mentioned, but they are far less important than the male gods.
• Ushas was the goddess of appearance of dawn and Aditi was the mother of all the gods. Demi-gods were Gandharvas, Maruts and Vishvedevas.
• The dominant mode of worshipping gods was through the recitation of prayers and offering of sacrifices. Prayers were of more importance during this period and were made both collectively and individually. Originally, every tribe or clan had a special god and prayers were offered in chorus by members of the whole tribe.
• There were no temples and no idol worship during the early Vedic period.
• God’s favour could also be won through sacrifices. A number of domestic and public sacrifices are mentioned in the Rigveda.
• Agni and Indra were invited to partake of sacrifices made by the whole tribe (Jana).
• Offerings of vegetables, barley, etc. were made to gods.
• In Rigvedic times, the process was not accompanied by any ritual or sacrificial formulae. Magical power of the words was considered not so important as it came to be in later Vedic times.
• Real development of a sacrificial cult took place in the second phase of Aryan expansion in India.
• Motive for worship was mainly for material gains such as praja (children), pasu (cattle), food, wealth, health, and for ending miseries of existence not spirtual uplift.
• The number of hymns attributed to different Vedic gods are, Indra: 250; Agni: 200; Soma: 120; Varuna: 12; Surya: 10; Pushan: 08; Vishnu: 06; Rudra: 03; Mitra: 01.



The Greek word “phyto” means plant and the Latin word “retmedium” means to cure or restore. Phyto-remediation is defined as “the process of restoration of quality of environment by the application of plants.” i.e. use of green plants based systems to detoxify or remove toxic, substances from contaminated air, water, soil and sediments, also called as green clean. Hence Phyto-remediation is the direct use of living green plants for in situ, or in place, removal, degradation, or containment of contaminants in soils, sludges, sediments, surface water and groundwater.
The plants exhibiting phyto-remediation should have following characteristics:
a) They should be fast growing plants.
b) They should have high biomass potential to accumulate large amount of toxicants. They normally show a property of binding the metal into their root tissues, transporting upward from their roots.
c) They should be locally growing tress to be able to adapt to the climatic conditions.
Types of Phyto-remediation
Following forms of phyto-remediation are applicable in different technologies:
a) Phyto-volatilization
Phyto-volatilization is the uptake and transpiration of a contaminant by a plant, with release of the contaminant or a modified form of the contaminant to the atmosphere from the plant through contaminant uptake, plant metabolism, and plant transpiration.
Certain transgenic plants reduce hazardous ionic and methylated forms of mercury to elemental mercury, which is then volatilized. Selenium phyto-remediation is also done by phyto-volatilization.
b) Phyto-stabilization
Phyto-stabilization is defined as (1) immobilization of a contaminant in soil through absorption and accumulation by roots, adsorption onto roots, or precipitation within the root zone of plants, and (2) the use of plants and plant roots to prevent contaminant migration via wind and water erosion, leaching, and soil dispersion.
In this form of phyto-remediation, agronomic techniques are used to stabilize contaminated sites (in-situ) i.e. checking the spread of contaminant in the different segments of environment, with following steps: Vegetation is grown on the site to reduce the movement of contaminants with water-runoff and soil erosion or Plants are grown to maximize the root uptake of contaminants.
c) Phyto-extraction
It is the most important form of phytoremediation in which toxic and non-biodegradable (persistant) contaminants e.g. Heavy metals are extracted from the environment by growing ‘green plants on the contaminated soil.
The toxic compounds are captured by the special compounds present in the plants, by the mechanism of chelating known as phytochelatins.
d) Rhizofiltration
Removal of toxic compounds in the contaminated water environment, by the filtration process of the roots of the plants is known as rhizofiltration. Roots of the plants act as biofilters i.e. roots help absorb toxic compound or metals from contaminated water and accumulate them. Contaminants are removed from the plants by harvesting (collecting from) the root biomass.
Example of Phytoremediation
Water hyacinth and salvinia are fast growing, weeds. Their higher productivity and resilience i.e. ability to accumulate very large amount of toxic substances (viz. heavy metals) make them ideal macrophytes for wastewater treatment (secondary and tertiary waste water treatment). The biomass is harvested- frequently to assure maximum productivity and removal of toxic substances.

Algal Bloom

Algal Bloom

Algae are photosynthetic microorganisms that are found in most aquatic habitats. Algae love runoff nutrients, and an algae bloom occurs when nutrient pollution and lots of sunlight create a rapid increase in the density of the algae. Algal blooms may occur in freshwater as well as marine environments.
When an algae bloom does happen, the stream, river, lake, or ocean becomes covered with algae, creating a thick mat of surface scum. Bright green colored blooms develop from cyanobacteria, which are also known as blue-green algae.
Broadly, bloom species can be classified into three different groups:
• Those which produce harmless water discolourations, but the dense bloom on decomposition can cause anoxia and lead to indiscriminate mortality of marine life,
• Species which produce potent toxins causing a variety of gastrointestinal and neurological illness to humans and
• Species which are not toxic to humans but harmful to fish and invertebrates by damaging or clogging their fish gills. The high–biomass producers are linked with production of scums and reduction of habitat for fish and shellfish.
Typically only one or a few phytoplankton species are involved and some blooms may be recognized by discoloration of the water resulting from the high density of pigmented cells.
Colors observed are green, yellowish-brown, or red. Bright green blooms may also occur. These are a result of blue-green algae, which are actually bacteria (cyanobacteria).
Freshwater algal blooms are the result of an excess of nutrients, particularly some phosphates. The excess of nutrients may originate from fertilizers, household cleaning products containing phosphorus. These nutrients can then enter watersheds through water runoff.  Excess carbon and nitrogen have also been suspected as causes. Presence of residual sodium carbonate acts as catalyst for the algae to bloom by providing dissolved carbon dioxide for enhanced photosynthesis in the presence of nutrients.
A harmful algal blooms (HAB) is an algal bloom that causes negative impacts to other organisms via production of natural toxins, mechanical damage to other organisms, or by other means. HABs are often associated with large-scale marine mortality events and have been associated with various types of shellfish poisonings.
People often get sick by eating shellfish containing toxins produced by these algae. Airborne HAB toxins may also cause breathing problems and, in some cases, trigger asthma attacks in susceptible individuals.
(HABs) involves toxic or otherwise harmful phytoplankton. Such blooms often take on a red or brown hue and are known colloquially as red tides.
Red tide is a term often used synonymously with HABs in marine coastal areas, however the term is misleading since algal blooms can be a wide variety of colors and growth of algae is unrelated to the tides.
Hence Impact of algal bloom are:
A. Public Health Concerns
• Exposure to algal toxins may occur through consumption of tainted water, fish, or shellfish; recreational activities; or inhalation of aerosolized toxins.
• Algal toxins are known to cause illness immediately (hours to days) after exposure. In addition, several algal toxins are believed to be carcinogens or to promote tumor growth, although more research on the effects of long-term exposure is needed.
B. Ecologic Concerns
• HABs may cause mortality of aquatic organisms because of low dissolved oxygen or algal toxins. Algal toxins also may cause mortality of terrestrial organisms using the water source.
• As more algae and plants grow, others die.This dead organic matter becomes food for bacteria that decompose it.With more food available, the bacteria increase in number and use up the dissolved oxygen in the water. When the dissolved oxygen content decreases, many fish and aquatic insects cannot survive.This results in a dead area.
C. Economic Concerns
• Economic concerns associated with HABs include increased drinking-water treatment costs, loss of recreational revenue, loss of aquacultural and fisheries revenue, and livestock sickness or fatalities.
• Taste-and-odor compounds are of particular concern to drinking-water suppliers because of customer dissatisfaction with malodorous drinking water.

Algae Fuel

Algae Fuel

Algae fuel is an alternative to liquid fossil fuels that uses algae as its source of energy-rich oils.
Like fossil fuel, algae fuel releases CO2 when burnt, but unlike fossil fuel, algae fuel and other biofuels only release CO2 recently removed from the atmosphere via photosynthesis as the algae or plant grew.
The Bio-energy Technologies Office’s Advanced Algal Systems Program is carrying out a long-term applied R&D strategy to increase the yields and lower the costs of algal biofuels by working with partners to develop new technologies, to integrate technologies at commercially-relevant scales, and conduct crosscutting analyses.
This will help researchers understand the potential and challenges of an algal biofuel industry ultimately capable of producing billions of gallons per year of renewable diesel, gasoline, and jet fuels.  These activities are integrated with the Office’s longstanding approach to accelerate the commercialization of lignocellulosic biofuels.
It will help in promoting sustainable and affordable algal biofuels.
• Algae benefit the environment: when algae for bio-fuel is grown, it absorbs carbon dioxide due to photosynthesis. This carbon dioxide is later released when burned as a fuel, therefore no net gain of carbon dioxide is released into the air.
• Algae is not harmful to the environment: it is non-invasive and the bio-fuel is produced in an earth friendly algae production plant.
• Algae is cheaper to produce than fossil fuels: algae can produce 10,000 gallons of oil per acre.
• Algae produces numerous byproducts: these include but are not limited to: pet food, fertilizer, feed stock, and even energy drinks.
• Algae can be converted into the three most important liquid fuel types: gasoline, diesel, and jet fuel.
• Algae fuel can be used in vehicles without converting them: the type of oil made by algae is usable in car, jet and other types of engines without having to change or replace them.
• Algae is renewable and affordable: “It is produced in the United States, has a low carbon footprint, is price-competitive, and fits seamlessly into our existing energy infrastructure”.
• Algae as a bio-fuel is expensive to produce because the research and development of algae bio-fuel is limited at this point in time, it is still relatively expensive to produce.
• Algae as bio-fuel would threaten Oil Company profits although some oil companies (Shell, Chevron, BP) are conducting research on this alternative energy source, they are not ready to fully commit to the idea of green crude.
• Growing algae can be risky because when algae is grown in a pond, it is cheaper to produce oil. However, the process can be disrupted by animals if not placed a closed, controlled system.

Sai Praveen

Do You Like This??? Then Hit Subscribe Button. You Will Get Every Post, Which Is Worth Reading

You are Visitor number