They are not extinct...
go extinct
Natural silk comes from silk worms while artificial silk is made of cotton. Natural silk has a beautiful sheen to it. Go to the links and see this beautiful silk fabric.
Only silk worms make silk so even though we can go to the moon and back, we need the silk worm to make silk as they are part of our environment.
By definition, all wild animals must breed in the wild, otherwise they go extinct.
The Przewalski never did go completely extinct. they were bred in zoos and re-released back into their homelands. The Tarpan on the other hand went completely extinct but they have 'recreated' the breed and released it into the wild.
Why did the dinosaurs go extinct? Humans will never go extinct!
Not likely. Those animals may still continue to exist as pets or in zoos.
If the wild boars went extinct the wild sows would cease to have offspring and the species would go extinct.If you mean "What happens if wild pigs go extinct?" then you would haven adjustment in the ecosystems where they live. Some predator species would find a replacement food or die out. Some plants which they eat would flourish. Some herbivores or omnivores whey complete with for food would flourish. All of these would change the local ecology, In areas where wild boars are really feral pigs which are escaped from farms - the ecology would return to closer to the pre-existing conditions. Farmers who find wild pigs to be detrimental to their crops might be happy.
Pandas are more known to be safe in captivity because they are an endangered species. There is more of a chance that Pandas will go extinct in the wild because we cant keep track of them.
They didn't. The remaining wild red wolves were placed in a captive breeding program. Today, 110 wild red wolves roam the swamplands of eastern NC.
The Tarpan went extinct in the wild in the late 1800's, and the last Tarpan in captivity died in 1876.
White tigers are all decended from a very small number of wild caught white tigers. There are very few if any white tigers currently in the wild. However as a white tiger can be born to two normal coloured tigers and is not a species in itself, it will go extinct when all tigers are extinct