Why did diseases have a disastrous impact on Aboriginal Australians after Europeans traveled to Australia.

Because they hadn’t had the centuries of exposure to them that Europeans had to allow them to build some resistance to them. Essentially they were brand new diseases, not just to Aboriginal Australians but to native people all over the world.

Explanation:

answer; utilitarian;

answer; have joints that fail from excess by early the accumulated effects of unnoticed infections,all of these things are possible for a person born without the ability to feel pain;