How Nature Works in Harmony Class 8 - Chapter 12 Curiosity

Q 1
Question
Refer to the given diagram (Fig. 12.19) and select the wrong statement.
(i) A community is larger than a population.
(ii) A community is smaller than an ecosystem.
(iii) An ecosystem is part of a community.
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Q 2
Question
A population is part of a community. If all decomposers suddenly disappear from a forest ecosystem, what changes do you think would occur? Explain why decomposers are essential.
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Q 3
Question
Selvam from Cuddalore district, Tamil Nadu, shared that his village was less affected by the 2004 Tsunami compared to nearby villages due to the presence of mangrove forests. This surprised Sarita, Shabnam, and Shijo. They wondered if mangroves were protecting the village. Can you help them understand this?
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Q 4
Question
Look at this food chain: Grass → Grasshopper → Frog → Snake. If frogs disappear from this ecosystem, what will happen to the population of grasshoppers and snakes? Why?
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Q 5
Question
In a school garden, students noticed fewer butterflies the previous season. What could be the possible reasons? What steps can students take to have more butterflies on campus?
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Q 6
Question
Why is it not possible to have an ecosystem with only producers and no consumers or decomposers?
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Q 7
Question
Observe two different places near your home or school (e.g., a park and a roadside). List the living and non-living components you see. How are the two ecosystems different?
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Q 8
Question
'Human-made ecosystems like agricultural fields are necessary, but they must be made sustainable.' Comment on the statement.
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Q 9
Question
If the Indian hare population (Fig. 12.20) drops because of a disease, how would it affect the number of other organisms?
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Project 1
Project
Plan a clean-up day at school or a nearby park. Wearing gloves and using bags, collect the litter you find. Discuss the kinds of waste you found. Which was the most common? How can we reduce such waste?
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Key Points
A clean-up survey shows plastic is usually the most common waste.
Key Points / Good Practices
Wear gloves and use separate bags for each type of waste.
Sort waste into plastic, paper, food and glass.
Count each type to find the most common one.
Plastic wrappers and bags are often the most common.
Reduce waste by reusing, recycling and avoiding single-use plastic.
Carry cloth bags and a reusable water bottle.
Sorting and reducing waste keeps our surroundings clean.

Project 2
Project
In Arunachal Pradesh, the Nyishi and Mishmi tribes treat the Tiger as sacred. In Chhattisgarh, the Baiga tribe worships the Bagesur Dev and believes the Tiger is the protector of the forest. Find out about other Indian tribes that have a special connection with animals.
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Key Points
Many Indian tribes protect animals through their beliefs and traditions.
Key Points / Good Practices
The Bishnoi community of Rajasthan protects blackbucks and trees.
The Warli tribe celebrates animals in their folk paintings.
The Apatani in Arunachal Pradesh protect their land and birds.
Many tribes treat sacred groves as protected forests.
These beliefs help conserve wildlife and biodiversity.
Find local examples and share them with the class.
Tribal traditions are a powerful force for conservation.

Project 3
Project
Pick a tree near your home or school. Observe it once a week for 4 weeks. Note any new leaves, flowers, fruits, or visiting birds and insects. Record your observations. You may even upload your findings to www.seasonwatch.in and become a young citizen scientist.
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Key Points
Regular tree-watching reveals how a tree changes with the seasons.
Key Points / Good Practices
Choose one tree and observe it at the same time each week.
Note new leaves, flowers, fruits and their numbers.
Record the birds and insects that visit the tree.
Use a simple table with date and observation columns.
Compare the four weeks to spot changes.
Upload findings to www.seasonwatch.in to share data.
Careful observation makes you a young citizen scientist.

Project 4
Project
Interact with farmers and record indigenous practices followed by them for sustainable farming. Create a sustainable herbal garden/natural farm at home or at school. It could be a group activity with students from different grades.
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Key Points
Indigenous practices and a herbal garden teach sustainable farming.
Key Points / Good Practices
Ask farmers about traditional methods like compost and crop rotation.
Record practices that use no synthetic chemicals.
Pick a small plot at home or school for the garden.
Plant herbs like tulsi, mint, neem and aloe vera.
Use organic compost and reuse kitchen waste.
Work in a group across grades and share the harvest.
Traditional wisdom plus a garden teaches real sustainability.

Project 5
Project
Look at Fig. 12.21 to understand the different farming practices adopted by farmers or you may also visit a nearby farm with an elderly person to observe the same. List a few suggestions in your notebook to improve farming practices by adopting eco-friendly and sustainable techniques. You can also make posters or model and display while participating in school functions, science fairs or Krishi Mela. The school may also invite agricultural scientists, farmers, and experts to discuss the prevalent farming practices with the students.
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Key Points
Observing real farms helps suggest eco-friendly, sustainable practices.
Key Points / Good Practices
Study the farm picture or visit a farm with an elder.
Note practices like composting, crop rotation and mixed cropping.
Suggest using organic manure instead of synthetic chemicals.
Recommend saving water and protecting natural predators.
Make posters or models for science fairs or Krishi Mela.
Invite farmers and agricultural scientists to share their knowledge.
Eco-friendly techniques keep farms productive and the soil healthy.