Question 1

In recent years the number of species driven to extinction has increased dramatically. Which of the following is not a reason for this?

Accepted Answer

Natural predation is a relationship between two animals in which one kills or hunts( predator) and other other is killed or hunted (prey). This is a natural process and helps in keeping control over the number of  prey species so that there is no imbalance in the ecosystem. This cannot be a reason for extinction of species as it is a natural and required process to prevent overpopulation of any one species.

Question 2

Which parameter of a population do ecologists measure to assess extinction risk for a population?

Accepted Answer

Extinction risk is usually assessed using ecological and demographic risk factors (Caughley1994). Data-intensive methods such as population survival analysis (Gilpin and Soulé 1986, Boyce 1992, Beissinger and Westphal 1998) are useful when  only one or a small number of populations are endangered.

Question 3

When a species goes extinct in one area, it is often desirable to reintroduce the species from other populations. A major problem with this approach is that

Accepted Answer

When alien species are introduced intentionally or intentionally for any purpose, some of them become invasive, causing the decline or extinction of native species. If a species becomes extinct in one area, it is often desirable to reintroduce the species from another population. The main problem with this approach is that populations  often adapt to local conditions and may not survive if moved to another location.

Question 4

Why do species extinctions matter?

Accepted Answer

Species extinction matters because, animals and plants depend upon each other, so the loss of one species will affect others within the complex web of relationships. There are many pharmaceutical products are derived from natural products, loss of species could mean loss of therapeutic drugs. Also soil erosion may increase if certain plants go extinct because some plants have a high soil holding capacity.

Question 5

________ ecology is a sub-discipline of conservation biology the goal of which is to mend damaged and degraded ecosystems.

Accepted Answer

Restoration ecology is the study which supports the practice of ecological restoration, the practice of renewing and restoring degraded, damaged, or destroyed ecosystems and habitats in the environment by frequent human interruption and action.

Question 6

Which of the following methods could be used to restore a population of animals from a few male and female individuals.

Accepted Answer

Captive breeding, also known as captive propagation, is the process of breeding plants and animals in controlled environments such as wildlife sanctuaries, zoos, botanical gardens and other shelters.

Question 7

Of the following organisms which has the highest conservation priority?

Accepted Answer

It is important to maintain the endemic species. Many of them are endangered due to habitat loss and other human invasions. It is important to preserve them, as they are not only unique to a particular area, but also important for biodiversity conservation.

Question 8

Which of the following statements is true concerning the relationship between humans and the rest of the living world?

Accepted Answer

Humans benefit from biodiversity as a source of food, medicine and raw materials. Biodiversity ecosystems benefit humans by cleaning water and pollinating crops. Wool comes from different types of sheep and  other species such as rabbits, alpaca and goats.

Question 9

The number of species that become extinct due to habitat destruction is greatest in _______ ecosystems with many______species.

Accepted Answer

Endemic and Tropical forests of all kinds are rapidly disappearing  as people clean up the natural landscape, give way to  farms and pastures,  harvest timber for construction and fuel, and  build roads and urban areas.

Question 10

Major causes of human-induced extinctions of species include all of the following, except

Accepted Answer

Captive breeding is the deliberate breeding and increasing number of wild animals in captivity.

Question 11

Which of the following is not a reason to protect biodiversity?

Accepted Answer

There are many reasons, to protect the biodiversity of an ecosystem, which can be grouped into three categories: narrowly utilitarian, broadly utilitarian, and ethical.

Question 12

Which of the following is not currently a major cause of species extinctions?

Accepted Answer

Climate change is predicted to be a major cause of extinction in the future. Climate change due to global warming is the regular increase in the overall temperature of the earth's atmosphere which is generally credited to the greenhouse effect caused by increased levels of harmful gases pollutants like carbon dioxide, CFCs, and other.

Question 13

A species that is found only in a particular region is said to be

Accepted Answer

A native or endemic species is the species that is found in a certain ecosystem due to natural processes, like natural distribution and evolution.

Question 14

Which of the following statements about species-area relationships and their consequences for extinction rates is false

Accepted Answer

Island populations are much more susceptible to extinction compared to mainland populations. Because If inbreeding and loss of genetic variation are involved, then genetic variation must be lower on average in island than mainland populations.

Question 15

Which of the following is true? (A) The biological wealth of our plant has been declining rapidly and the accusing finger is clearly pointing to human activities (B) The colonisation of tropical pacific Island by humans is said to have led to the extinction of more than 2,000 species of native bird (C) The IUCN Red list (2004) documents the extinction of 784 species in last 500 years

Accepted Answer

With 7 billion people on the planet, the demand for global resources continues to grow. This is an excessive and unnecessary consumption of resources. Deforestation and ecosystem destruction lead to the  loss of biodiversity. Human colonisation leads to usage of the natural resource and also overexploitation and hamper of the biodiversity. One such example is the colonisation of tropical pacific Island by humans is said to have led to the extinction of more than 2,000 species of native bird. The IUCN Red List (2004) documents the extinction of 784 species in the last 500 years. The list includes 338 vertebrates, 359 invertebrates, and 87 plants. Some examples of recent extinctions include the dodo (Mauritius), quagga (Africa), thylacine (Australia), Steller’s Sea Cow (Russia) and three subspecies (Bali, Javan, Caspian) of the tiger.

Question 16

Which one the following is false about Habital loss and fragmentation?

Accepted Answer

The most dramatic examples of habitat loss come from the rainforest. Today, these rainforests cover only 6%, before these rainforests covered more than 14% of the Earth's land surface. They will be destroyed soon.

Question 17

Term biodiversity was utilized to describe the combined diversity at all the levels of biological organisation by -

Accepted Answer

Wilson defines biodiversity as everything that lives on Earth, and the rest as the physical world. He laments the fact that  many of us are very concerned about the physical world and seem to be working hard to get the physical ones to undermine the living world and biodiversity.

Question 18

Global species diversity and land area covered by India with respect to world is -

Accepted Answer

Global biodiversity is referred to as the measure of biodiversity on planet Earth and is defined as the total variability of life forms. India has only 2.4 per cent of the world's land area, its share of the global species diversity is an impressive 8.1 per cent.

Question 19

Which of the following factor has not aided in high species diversity of tropics?

Accepted Answer

The tropical environment is less seasonal, relatively  constant and predictable. Seasonal fluctuations are negligible. There are no bad seasons in the tropics. A continuous and favorable environment helps tropical organisms to become more niche-focused and diverse.

Question 20

Anthroprogenic extinction is called

Accepted Answer

The Holocene extinction, or the sixth mass extinction or Anthropocene extinction, is an ongoing extinction event of species during the present Holocene epoch (with the more recent time sometimes called Anthropocene) as a result of human activity.

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