Answer :

parrot
50 years ago nature was considered as part of life now it is considered as a helpful thing . humans before used it carefully as not to destroy ,but now destroying nature
became less important than technology development . there was not much need of factories therefore not much air and water pollution was caused.animal killing was only for food before but now it is being done for horns ,for making ornaments etc...
pics: before 50 years ,after 50 years
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