SCIENCE PROJECT

PPT ON EXTINCT SPECIES

BY M.Karthik

Class VIII ‘B’

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Contents

Biodiversity Ecosystem Threats to Biodiversity Classification by IUCN Extinct Species

Dodo Smilodon Pleuromeia Irish Elk

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Biodiversity

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What Is Meant By Biodiversity?

• Biodiversity means the variety of plants and animals that live in a particular region or habitat interacting with one another.

• In short, biodiversity defines the biological richness of an ecosystem.

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What Is Meant By Ecosystem?

• An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system.

• These biotic and abiotic components are regarded as linked together through nutrient cycles and energy flows.

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What Are The Threats To Biodiversity?

The major threats to biodiversity are:

Deforestation Over Exploitation Climate Changes

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How does deforestation affect biodiversity?Human activities lead to the removal of vegetation cover, displacement of fauna and soil erosion.

Soil erosion makes the land infertile as humus gets removed and the hard, rocky surface get exposed.

This cause desertification and renders the land unsuitable for growth of any vegetation.

It also affects the habitat of animals.

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Illegal hunting or poaching of wild animals is another major threat to biodiversity.

There are three types of endangerment- Threatened Endangered Vulnerable• Extinct species are the ones which are

completely wiped out of our planet.

How does over exploitation affect

biodiversity?

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How does climatic changes affect biodiversity?

With increasing air pollution amounting to global warming, the polar ice caps are melting.

As a result the sea level is increasing slowly. This disturbs the balance in the ecosystem.

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Classification by IUCN(International Union

for Conservation of Nature)• Normal Species: Species whose population levels are

considered to be normal fortheir survival, such as cattle , sal, pine, rodents, etc.

• Endangered Species: These are species which are in danger of extinction. The survival of such species is difficult if the negative factors that have led to a decline in their population continue to operate. The examples of such species are black buck, crocodile, Indian wild ass, Indian rhino, lion tailed macaque, etc.

• Vulnerable Species: These are species whose population has declined to levels from where it is likely to move into the endangered category in the near future if the negative factors continue to operate. The examples of such species are blue sheep, Asiatic elephant, Gangetic dolphin, etc.

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Classification by IUCN(International Union

for Conservation of Nature)• Rare Species: Species with small population may move

into the endangered or vulnerable category if the negative factors affecting them continue to operate. The examples of such species are the Himalayan brown bear, wild Asiatic buffalo, desert fox and hornbill, etc.

• Endemic Species: These are species which are only found in some particular areas usually isolated by natural or geographical barriers. Examples of such species are the Andaman teal, Nicobar pigeon, Andaman wild pig, mithun in Arunchal Pradesh.

• Extinct Species: These are species which are not found after searches of known or likely areas where they may occur. A species may be extinct from a local area, region, country, continent or the entire earth. Examples of such species are the Asiatic cheetah, pink head duck.

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Extinct Species

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Extinct SpeciesSym

bol• The circle signifies the planet, while the hourglass inside serves as a warning that time is rapidly running out for many species.

• The world is currently undergoing a mass extinction event, and this symbol is intended to help raise awareness of the urgent need for change in order to address this crisis.

• Estimates are that somewhere between 30,000 and 140,000  species are becoming extinct every year in what scientists have named the Holocene, or Sixth Mass Extinction.

• This ongoing process of destruction is being caused by the impact of human activity.

• Within the next few decades approximately 50% of all species that now exist will have become extinct.

• Such a catastrophic loss of biodiversity is highly likely to cause widespread ecosystem collapse and consequently render the planet uninhabitable for humans.

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Dodo• The dodo (Raphus cucullatus) is

an extinct flightless bird that was endemic to the island of Mauritius, east of Madagascar in the Indian Ocean.

• Its closest genetic relative was the also extinct Rodrigues solitaire, the two forming the subfamily Raphinae of the family of pigeons and doves.

• The closest extant relative of the dodo is the Nicobar pigeon.

• A white dodo was once incorrectly thought to have existed on the nearby island of Réunion.

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SmilodonSmilodon Smilodon is an extinct genus of machairodont felid.

It is perhaps the best known saber-toothed cat and lived in North America during the Pleistocene epoch.

One of the largest collections of its fossils has been obtained from the La Brea Tar Pits.

Smilodon was more robustly built than any modern cat, with particularly well-developed forelimbs and exceptionally long upper canines.

Its jaw had a bigger gape than modern cats and its upper canines were slender and fragile, being adapted for precision killing.

These attributes made Smilodon a specialized hunter of large herbivores, such as bison and camels.

Smilodon is an extinct genus of machairodont felid.

It is perhaps the best known saber-toothed cat and lived in North America during the Pleistocene epoch.

One of the largest collections of its fossils has been obtained from the La Brea Tar Pits.

Smilodon was more robustly built than any modern cat, with particularly well-developed forelimbs and exceptionally long upper canines.

Its jaw had a bigger gape than modern cats and its upper canines were slender and fragile, being adapted for precision killing.

These attributes made Smilodon a specialized hunter of large herbivores, such as bison and camels.

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Pleuromeia Pleuromeia  Pleuromeia is a genus of extinct spore-trees belonging to the

order Pleuromeiales and class Isoetopsida. It was one of the most common plants during the recovery from the Permian-Triassic extinction event.

Unlike other arborescent lycopsids of the Carboniferous Period (about 359 million to 299 million years ago), such as Lepidodendron and Sigillaria, Pleuromeia had a four-lobed bulblike base rather than a branching underground rhizome.

A crown of long, thin leaves persisted near the growing tip of the trunk. Leaves and leaf bases were lost from lower portions of the plant.

Like its relatives, Pleuromeiareproduced by spores. Some species produced a single large cone at the trunk apex, and others may have produced many smaller cones.

The genus was widely distributed, and specimens are known from Russia, Europe, China, and Australia.

Pleuromeia is a genus of extinct spore-trees belonging to the order Pleuromeiales and class Isoetopsida. It was one of the most common plants during the recovery from the Permian-Triassic extinction event.

Unlike other arborescent lycopsids of the Carboniferous Period (about 359 million to 299 million years ago), such as Lepidodendron and Sigillaria, Pleuromeia had a four-lobed bulblike base rather than a branching underground rhizome.

A crown of long, thin leaves persisted near the growing tip of the trunk. Leaves and leaf bases were lost from lower portions of the plant.

Like its relatives, Pleuromeiareproduced by spores. Some species produced a single large cone at the trunk apex, and others may have produced many smaller cones.

The genus was widely distributed, and specimens are known from Russia, Europe, China, and Australia. C

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Irish ElkIrish Elk The Irish elk (Megaloceros giganteus ) was a species

of Megaloceros and one of the largest deer that ever lived. Its range extended across Eurasia, from Ireland to northern Asia and Africa, but a related form is recorded from China during the Late Pleistocene.

The most recent remains of the species have been carbon dated to about 7,700 years ago in Siberia.

 Although most skeletons have been found in Irish bogs, the animal was not exclusively Irish and was not closely related to either of the living species currently called elk - Alces alces (the European elk, known in North America as the moose) or Cervus canadensis(the North American elk or wapiti).

Recent phylogenetic analyses support the idea of a sister-group relationship between fallow deer (Dama dama) and the Irish Elk. For this reason, the name "Giant Deer" is used in some publications.

The Irish elk (Megaloceros giganteus ) was a species of Megaloceros and one of the largest deer that ever lived. Its range extended across Eurasia, from Ireland to northern Asia and Africa, but a related form is recorded from China during the Late Pleistocene.

The most recent remains of the species have been carbon dated to about 7,700 years ago in Siberia.

 Although most skeletons have been found in Irish bogs, the animal was not exclusively Irish and was not closely related to either of the living species currently called elk - Alces alces (the European elk, known in North America as the moose) or Cervus canadensis(the North American elk or wapiti).

Recent phylogenetic analyses support the idea of a sister-group relationship between fallow deer (Dama dama) and the Irish Elk. For this reason, the name "Giant Deer" is used in some publications.

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