Biodiversity Flashcards
For many taxonomic groups, species inventories are more complete in……….. than in…….. countries
temperate
tropical
Some extreme estimates range from…… to…….. million
20 to 50 million
A more conservative and scientifically sound estimate made by Robert May places the global species diversity at about……..
7 million.
More than………. per cent of all the species recorded are animals, while plants comprise no more than……..per cent of the total.
Here the plant group includes algae, fungi, bryophytes, gymnosperms and angiosperms
70
22
Among animals…….. are the most species-rich taxonomic group, making up more than…… per cent of the total
insects
70
Out of every 10 animals on this planet, 7 are insects
True
The number of fungi species in the world is more than the combined total of the species of
(4)
Fishes
Amphibians
Reptiles
Mammals
Invertebrates order
Insects > others > mollusca > crustacean
Vertebrates order
Fishes > birds > reptiles > amphibian > mammals
Plants group order
Fungi > angiosperms > algae > moss=ferns > lichens
Assertion: Biologists are not sure about how many prokaryotic species there might be.
Reason; The conventional taxonomic methods are not suitable for identifying microbial species and many species are simply not culturable under laboratory conditions.
Although India has only…… per cent of the world’s land area, its share of the global species diversity is an impressive…… per cent
2.4
8.1
Nearly………. species of plants and twice as many of animals have been recorded from India.
45,000
If we accept May’s global estimates, only……. per cent of the total species have been recorded so far
22
In India probably more than……… plant species and more than………. animal species yet to be discovered and described
1,00,000
3,00,000
In general, species diversity……. as we move away from the equator towards the poles
decreases
Colombia located near the equator has nearly………. species of birds while New York at 41° N has……. species
1,400
105
Greenland at 71° N only…… species of birds
56
India, with much of its land area in the tropical latitudes, has more than……. species of birds.
1,200
A forest in a tropical region like Equador has up to…….. times as many species of vascular plants as a forest of equal area in a temperate region like the Midwest of the USA
10
The largely tropical Amazonian rain forest in South America has the greatest biodiversity on earth
Give account of species here (7) categories
40,000 species of plants
3,000 of fishes
1,300 of birds
427 of mammals
427 of amphibians
378 of reptiles
more than 1,25,000 invertebrates
Scientists estimate that in these rain forests there might be at least…….. insect species waiting to be discovered and named.
two million
German naturalist and geographer………… during his exploration of South American jungles observed that within a region species richness increased with increasing explored area, but only up to a limit.
Alexander von Humboldt
A stable community should 3 attributes
not show too much variation in productivity from year to year
it must be either resistant or resilient to occasional disturbances (natural or man-made)
it must also be resistant to invasions by alien species.
David Tilman found that plots with more species showed less year-to-year variation in total biomass. He also showed that in his experiments, increased diversity contributed to higher productivity.
True
The ‘rivet popper hypothesis’ is given by……..
Paul Ehrlich.
The colonisation of tropical Pacific Islands by humans is said to have led to the extinction of more than……. species of native birds.
2,000
The IUCN Red List (2004) documents the extinction of………. species in the last 500 years
784 including 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)
three subspecies (Bali, Javan, Caspian) of tiger.
The last twenty years alone have witnessed the disappearance of…… species
27
The extinctions across taxa are not random; some groups like….
.. appear to be more vulnerable to extinction
amphibians
More than…… species world-wide are facing the threat of extinction.
15,500
Presently……… per cent of all bird species……per cent of all mammal species……per cent of all amphibian species and………per cent of all gymnosperm species in the world face the threat of extinction.
12
23
32
31
The current species extinction rates are estimated to be ……..times faster than in the pre-human times
100 to 1,000
Ecologists warn that if the present trends continue, nearly half of all the species on earth might be wiped out within the next……. years
100
Once covering more than……… per cent of the earth’s land surface, these rain forests now cover no more than…….per cent
14
6
Steller’s sea cow and Passenger pigeon extinct due to
Over exploitation
The Nile perch introduced into Lake Victoria in east Africa led eventually to the extinction of an ecologically unique assemblage of more than……… species of cichlid fish in the lake
200
Invasive weed species
Carrot grass= Parthenium
Lantana
water hyacinth= Eicchornia
The recent illegal introduction of the African catfish …………. for aquaculture purposes is posing a threat to the indigenous catfishes in our rivers.
Clarias gariepinus
More than…… per cent of the drugs currently sold in the market worldwide are derived from plants
25
………….. species of plants contribute to the traditional medicines used by native peoples around the world
25,000
Bio prospecting refers to:
exploring molecular, genetic and species-level diversity for products of economic importance
Amazon forest is estimated to produce, through photosynthesis……… per cent of the total oxygen in the earth’s atmosphere
20
Initially…….. biodiversity hotspots were identified but subsequently ……….. more have been added to the list, bringing the total number of biodiversity hotspots in the world to……..
25
9
34
Three of these hotspots – ……./……/…….. cover our country’s exceptionally high biodiversity regions
Western Ghats and Sri Lanka
Indo-Burma
Himalaya
Although all the biodiversity hotspots put together cover less than….. per cent of the earth’s land area, the number of species they collectively harbour is extremely high and strict protection of these hotspots could reduce the ongoing mass extinctions by almost…… per cent.
2
30
In India, ecologically unique and biodiversity-rich regions are legally protected as
(3)
biosphere reserves
national parks
sanctuaries
India now has……. biosphere reserves……. national parks and…… wildlife sanctuaries
14
90
448
The sacred groves are found in
Khasi and Jaintia Hills in Meghalaya
Aravalli Hills of Rajasthan
Western Ghat regions of Karnataka and Maharashtra
Sarguja, Chanda and Bastar areas of Madhya Pradesh.
Zoological parks, botanical gardens and wildlife safari parks are forms of……….. conservation
Ex situ
The historic Convention on Biological Diversity ……………….. held in Rio de Janeiro in………..called upon all nations to take appropriate measures for conservation of biodiversity and sustainable utilisation of its benefits
The Earth Summit
1992
In a follow-up, the World Summit on Sustainable Development held in…………. in Johannesburg, South Africa………… countries pledged their commitment to achieve by 2010, a significant reduction in the current rate of biodiversity loss at global, regional and local levels.
2002
190
