An endangered species is a type of organism that is threatened by extinction. Species become endangered for two main reasons: loss of habitat and loss of genetic variation. A loss of habitat can happen naturally. Dinosaurs, for instance, lost their habitat about 65 million years ago. The hot, dry climate of the Cretaceous period changed very quickly, most likely because of an asteroid striking the Earth. The impact of the asteroid forced debris into the atmosphere, reducing the amount of heat and light that reached Earth’s surface. The dinosaurs were unable to adapt to this new, cooler habitat. Dinosaurs became endangered, then extinct. Human activity can also contribute to a loss of habitat. Development for housing, industry, and agriculture reduces the habitat of native organisms. This can happen in a number of different ways. Development can eliminate habitat and native species directly. In the Amazon rain forest of South America, developers have cleared hundreds of thousands of acres. To “clear” a piece of land is to remove all trees and vegetation from it. The Amazon rain forest is cleared for cattle ranches, logging, and urban use. Development can also endanger species indirectly. Some species, such as fig trees of the rain forest, may provide habitat for other species. As trees are destroyed, species that depend on that tree habitat may also become endangered. Tree crowns provide habitat in the canopy, or top layer, of a rainforest. Plants such as vines, fungi such as mushrooms, and insects such as butterflies live in the rain forest canopy. So do hundreds of species of tropical birds and mammals such as monkeys. As trees are cut down, this habitat is lost. Species have less room to live and reproduce. Based on the passage above choose the correct option for the following questions.
According to the passage, which of the following is the likely reasoning for the dinosaurs becoming endengared and then extinct?
Asteroid striking the Earth
Understanding Dinosaur Extinction Based on the Passage
The passage discusses how species become endangered, focusing on two main reasons: loss of habitat and loss of genetic variation. It provides examples of both natural and human-induced habitat loss.
One prominent example used in the passage for natural habitat loss is the extinction of the dinosaurs. The passage specifically describes the events leading to the dinosaurs becoming endangered and then extinct.
According to the text:
- The climate during the Cretaceous period was hot and dry.
- This climate changed very quickly.
- The most likely cause for this rapid climate change was "an asteroid striking the Earth".
- The asteroid impact sent debris into the atmosphere, reducing sunlight and heat, making the Earth cooler.
- The dinosaurs could not adapt to this new, cooler habitat.
- Because they could not adapt to the changed habitat, the dinosaurs became endangered, and subsequently, extinct.
Therefore, based on the information provided directly in the passage, the primary reason cited for the dinosaurs becoming endangered and then extinct is the impact of an asteroid striking the Earth, which led to significant climate change and habitat loss.
Revision Table: Key Concepts from the Passage
| Concept | Description Based on Passage |
|---|---|
| Endangered Species | Organisms threatened by extinction. |
| Reasons for Endangerment | Loss of habitat, Loss of genetic variation. |
| Natural Habitat Loss Example | Dinosaurs adapting to climate change after asteroid strike. |
| Human-caused Habitat Loss Example | Clearing land for development (housing, industry, agriculture), impacting dependent species (e.g., fig trees in Amazon). |
| Dinosaur Extinction Cause (Passage) | Asteroid striking Earth leading to rapid climate change & habitat loss. |
Additional Information: Endangered Species & Habitat Loss
Understanding why species become endangered is crucial for conservation efforts. The passage highlights that habitat loss is a major factor, affecting species by reducing the space they need to live and find resources like food and shelter, and by limiting their ability to reproduce successfully.
Genetic variation is also important because it provides a population with the diversity needed to adapt to changing environmental conditions. When genetic variation is lost, a species becomes more vulnerable to diseases and environmental changes, increasing its risk of extinction.
Similar Questions
Indian food is rich in ______.
According to the passage, what has Middle Eastern and Central Asian influenced in India?
According to the passage, choose the correct synonym of the word ‘catalyst’.
How was Indian cuisine able to influence other cuisines across the world?
According to the passage, which of the following are the two main reasons of species becoming endangered species?
Which of the following statements is not true?
Which of the following word is the ANTONYM of the word ‘native’ used in the passage?
Which of the following do not live in the canopy of the Amazon rain forests?
Which of the following statement is correct according to the passage given above?
- Saint Kabir believed that saintly people:
Important Questions from Reading Comprehension
What best describes bulimia?
When an activity requires too much effort we feel:
What kind of attitude does the writer advocate for a life of fulfilment?
Why did the young lady approach the piano teacher for music lessons?
What does 'bread making' attitude consist of?
