If there are effects of linolenic acid on mammalian torpor, then the second sentence is still true. Life science is based on observational evidence, and since

If there are effects of linolenic acid on mammalian torpor, then the second sentence is still true. Life science is based on observational evidence, and since humans are some mammals who have never been observed to undergo torpor, effects observed inducing mammalian torpor do not apply to humans. They're not making a positive evolutionary statement about human torpor never existing, just that any observed effects from linolenic acid on mammalian torpor do not apply to humans the way the other person was implying it does.