Why don't dogs or cats become hoarse after barking or meowing for extended periods of time?

I have heard dogs bark for literally hours at a stretch, yet they never grow hoarse. My cats can meow for the 20 minute ride to the vet and the 20 minute ride home with no noticeable effect on their “voices.” What is it about their physiology that allows this?

I’m going to bed now, but look forward to being better informed in the morning!