Evolution and its processes
Class 10, 11 & 12
Key Learning Objectives
1 Hour (Approximately)
- THE MISSION
Imagine in the game, you have the special skill of listening to the past through various fossils and archaeological ruins and what they want to convey. They tell you the history of the species, the process of evolution. You then as a person with special skills start to use Natural and Artificial selection and create a lot of species that can survive and thrive. Bringing together your understanding of evolutionary relationships and human evolution, the gamer plans to develop an universe where through Natural and Artificial Selection all forms of organisms and species are formed for growth and development and the player gains 500 points during the steps of this extensive process.
- It is the phenomenon by which a favourable trait in a population of a species is selected.
- Changing natural conditions exert equal pressure on all the existing species.
- The species/organisms which are better adapted to the changing conditions survive and reproduce i.e. selected by nature and species/organisms which cannot adapt perish i.e. rejected by nature..
Natural selection can play an important role in deciding the traits that survive in a population. However, random fluctuations in gene variants are seen on many occasions. This phenomenon is known as genetic drift. Thus, genetic drift is a change in the frequency of an existing allele in a small population.
Genetic drift may cause a gene variant to disappear from the population and thus reduce genetic variation.
It is the process of formation of a new species from existing ones due to several evolutionary forces like genetic drift, isolation of populations, natural selection, etc. Speciation leads to diversity in the ecosystem and the diversity and diversity lead to evolution.
Gene flow is the transfer of genes from one population to the next.
A population is a community or a group of animals, plants or any living organism that can reproduce with each other and have fertile, viable offspring.
Charles Darwin also called “Father of Evolution” was an English Naturalist and Biologist. Five years expedition in a ship called HMS Beagle to Galapagos Island helped him write his theory of evolution. In 1859 he published a book called Origin of Species, in which he put his theory of evolution in detail.
- Evolution & Fossils
Evolution is a tangible change in the heritable characteristics of a population over several generations. These changes can give rise to a new species or the species might change themselves to become better adapted to the surrounding environment.
Origin of species
After a successful expedition on HMS Beagle, Charles Darwin wrote a book on what he observed at the Galapagos Islands. In the book named ‘The Origin of Species’, he wrote a detailed theory of evolution which was mostly based on Natural Selection.
Origin of life – Haldane’s theory
JBS Haldane was a British Scientist who theorized that life originated from organic and lifeless matter. His theory was proved to be correct by Urey and Miller’s experiment. It was called the theory of abiogenesis.
Evolutionary evidence – fossils
There are plenty of pieces of evidence to support the theory of evolution. Fossils happen to be the biggest of them. Fossils are the preserved remains of ancient animals or plants that died millions of years ago.
The fossils help us understand the anatomy and even physiology of these organisms and understand how evolution worked and led to the formation of organisms that we see today.
Formation of Fossils
Fossils are important pieces of evolutionary evidence and are formed by the following steps:
- Organisms die and they get buried in mud and silt.
- The soft tissues of the body get quickly leaving behind the hard bones or shells
- Over time sediments build over it and harden into rock
- As the bones decay, mineral seep in to replace the contents cell by cell, process called as petrification
- If bones decay completely, it leaves behind the cast of the animal.
Evolutionary relationships of animals can be deduced by studying the homologous organs and analogous organs.
Homologous organs are those which have a similar structure but different function.
- Wings of birds and forelimbs of mammals: they have similar structure but are modified to suit different functions
- A tendril of pea plant and spine of barberry plant: both are modified leaves, but perform different functions.
Analogous organs are those which have a similar function but a different structure and origin too.
- Wings of bats, birds and wings of insects: both are used for flying, but structurally are very different
- Leaves of opuntia and peepal: both perform photosynthesis, but leaves of Opuntia are modified stem whereas peepal leaves are normal leaves.
Evolution by stage
Evolution is a slow process and does not happen overnight. There are several stages in the evolution of almost every animal that we see today. Complexities do not evolve suddenly, but evolve bit by bit and may have limited use at certain stages. This gradual evolutionary process is called evolution by stages.
Sometimes a single species can evolve into several different species due to artificial selection. E.g. the cabbage family. A single ancestor in the cabbage family gave rise to several different species due to the selection of different traits.
The evolutionary relationship among different biological species is called phylogeny. It gives rise to an evolutionary tree. In molecular phylogeny these relationships are studied at the hereditary molecular level, mainly using DNA sequences. It involves the analysis of DNA composition and gene comparison between different species.
- Human Evolution
Humans are known to belong to the primate family. Humans today have a very close genetic connection to chimps and other primates. While the complete evolutionary process of Humans from Primates is still a mystery, a larger picture of human evolution has been formed. Some of the ancestors of Humans include Dryopithecus, Ramapithecus, Australopithecus, Homo erectus, Homo sapiens neanderthalensis, Cro-magnon man, and finally us, the Homo sapiens. Human evolution traces back to Africa. Then they migrated all over the world
- Problem statement
Imagine in the game, you have the special skill of listening to the past through various fossils and archaeological ruins and what they want to convey. They tell you the history of the species, the process of evolution. You then as a person with special skills start to use Natural and Artificial selection and create a lot of species that can survive and thrive. Bringing together your understanding of evolutionary relationships and human evolution, the gamer plans to develop a universe where through Natural and Artificial Selection all forms of organisms and species are formed for growth and development and the player gains 500 points during the steps of this extensive process.
- Game design overview
Imagine in the game, you have the special skill of listening to the past through various fossils and archaeological ruins and what they want to convey. They tell you the history of the species, the process of evolution. You then as a person with special skills start to use Natural and Artificial selection and create a lot of species that can survive and thrive. Bringing together your understanding of evolutionary relationships and human evolution, the gamer plans to develop a universe where through Natural and Artificial Selection all forms of organisms and species are formed for growth and development and the player gains 500 points during the steps of this extensive process. The Player has to strategically design the game in such a way that all the steps of this process has to be successfully completed.
- How to design the game?
- Step I
Imagine in the game, you have the special skill of listening to the past through various fossils and archaeological ruins and what they want to convey. They tell you the history of the species, the process of evolution.
Hint: The history of our species and process of evolution has to be visually recorded with audio, as the world is drastically deteriorating and hence these lessons will greatly help in bringing about a civilisation. There is a severe UV rays’ penetration into planet earth that is destroying all forms of life on earth and objects and it is your responsibility to protect all the records of the experiences you have received from the fossils by storing it in light proof objects. Successful completion of this step of this game gives you 200 points in 20 minutes. If the particular step of this process is not completed within 20 minutes, UV rays will destroy all the forms of documentation.
- Step II
In the next level of the game, you are tasked with building an entire ecosystem of living organisms through Natural selection, as there has been a huge calamity where the harmful UV rays have destroyed all the living organisms and you are in charge of creating an entire new world.
Hint: Using Natural selection and the knowledge the gamer has, an entire world has to be created and there will be various obstacles along the way as some of the earlier organisms that were present on earth have been converted into soul sucking demons that are out to destroy the newly created organisms which are strong and powerful. It is the job of the gamer to strategically design in such a way that the gamer invents a powerful medicine which when the demons are forcefully made to take and they get converted into humans. You will have to carry this forward for 10 such demons gaining 200 points. If the second level of the game is not completed within 10 minutes, the demons double in size and they destroy all the organisms created.
- Step III
There are certain organisms that have to be created through artificial selection and this completes the game.
Hint: This level of the game should be completed in 10 minutes and you will gain 100 points totalling the points to 500 and also helping you receive a badge of honour.
Learning Objective Based Evaluation (0-1)
Higher Order Thinking Skills
Learning Objective Based Evaluation Total Score
Higher Order Thinking Skills Total Score
Learning Objective Based Evaluation
1 point Questions:
Q1. Who is called the Father of Evolution?
- Charles Darwin
- JBS Haldane
- None of the above
Q2. Which of the following statements refers to homologous organs?
- similar structure but different function.
- Different structure and different function
- Different structure but similar function
- None of the above
Q3. What family does humans belong to?
- Primate family
- Canine family
- None of the above
Q4. Which continent does Human Evolution trace back to?
- United Kingdom
- None of the above
Evaluation of HOTS (Higher Order Thinking Skills)
Identification of the Problem Statement:
Q5. What is the goal of the game that you have designed? (1 point)
Q6. Does the game designed solve the problem? Justify your answer. (1 point)
Solution of the Problem Statement:
Q7. What are the reasomns? (1 point)
Q8. What are the reasons that freedom is important to a country? (1 point)
Innovation in the Problem Statement:
Q9. What are the innovative aspects of the solution for which the game is designed? (2 points)
Creativity in the Game Design:
Q10. Describe and explain the unique design elements used in the game. (2 points)
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