"where a cause can be attributed."?

[japanjapan]

Dear teachers,
Please read the following sentence:
Hunting is thought to be responsible for more than one-quarter of all known extinctions where a cause can be attributed.

What does "where a cause can be attributed" mean?
Does it mean "...extinctions where reasons can be found"?
Are there extinctions where reasons have not been found by humans yet?

I am puzzled.
please help.

thanks a million.

yours
japanjapan

[phukos]

Originally Posted by japanjapan

Dear teachers,
Please read the following sentence:
Hunting is thought to be responsible for more than one-quarter of all known extinctions where a cause can be attributed.

What does "where a cause can be attributed" mean?
Does it mean "...extinctions where reasons can be found"?
Are there extinctions where reasons have not been found by humans yet?

I am puzzled.
please help.

thanks a million.

yours
japanjapan

Yes, it does mean what you think it means.
There are many cases of species extinction to which no known cause can be attributed.
Thanks!