Write short note on Prospects for insect conservation.
Answers
Most of the animals in this group are extinct. The egg-laying monotremes are known from fossils of the Cretaceous and Cenozoic periods; they are represented today by the platypus and several species of echidna.
The names Prototheria, Metatheria, and Eutheria (meaning "first beasts", "changed beasts", and "true beasts", respectively) refer to the three mammalian groupings of which we have living representatives. Each of the three may be defined as a total clade containing a living crown-group (respectively the Monotremata, Marsupialia and Placentalia) plus any fossil species which are more closely related to that crown-group than to any other living animals.
The threefold division of living mammals into monotremes, marsupials and placentals was already well established when Thomas Huxley proposed the names Metatheria and Eutheria to incorporate the two latter groups in 1880. Initially treated as subclasses, Metatheria and Eutheria are by convention now grouped as infraclasses of the subclass Theria, and in more recent proposals have been demoted further (to cohorts or even magnorders), as cladistic reappraisals of the relationships between living and fossil mammals have suggested that the Theria itself should be reduced in rank.[2]
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The insect fauna of Europe and indeed the entire invertebrate fauna of the region has been subjected to an immense variety of severe changes of environmental conditions, habitat suitability and other threats to their existence. Most of these animals also remain at the bottom of the league in public profile and conservation status in modern European society and environmental policy.
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