Scientists do not know why bobcats have tufted ears. That, I am afraid, is the answer. However, readers of this article will want to see a fuller answer. Therefore, I will speculate why bobcats have tufted ears.
One website says that they improve hearing or they allow the cat to detect things above their head. Neither of these suggestions seem believable.
There is another wild cat species with the most prominent ear tufts of all the cats: the caracal. A lady, Deborah-Ann Milettte, in America had a pet caracal. She knew the cat well. Her suggestion about why these ear tufts exist is more believable.
“I learned with my quite sociable Israeli Caracal, Tesha. She would flip an ear when I walked to the door. I labeled it acceptance. So I chose to take my fingers in a “V” shape and flip one finger back to her. She would reply with one ear flip then the other ear would flip, OK we had acknowledgment.”
See the article written by her:
They are part of the signalling process, a form of communication. We know that a cat’s ear flaps (pinnae) can be used to send a signal to other cats as well as collect sounds, and this applies to domestic cats too. The ear tufts make the ear more prominent and therefore make the signal more noticeable and definite.
I believe that this is a more likely reason for their existence. It should also be noted that all domestic cats have ear tufts to a certain extent. They are hardly noticeable in some domestic cats and in others such as the purebred Maine Coon they have been selectively bred to be large and prominent. They are called ‘lynx tipped ears’ in the Maine Coon.
The point that I’m making is that they exist in any case and if they are particularly long it may be the case that there is no Darwinian reason as to why they evolved. They may simply exist because the bobcat and particularly the lynx have longer fur. However, it is probably more likely that there is a reason. Another point worth noting is that they are dark.
The bobcat is part of the Lynx family of cats. Lynx cats live in areas where there’s lots of snow. There may be a connection between the dark ear tufts and the white snow. This would make the signalling provided by the ear movements even more noticeable. However, in North America bobcats don’t venture as far north as the Canada lynx because they have relatively poor thermoregulatory abilities.
To recap: bobcats and lynx cats probably have tufted ears for communication purposes between themselves.
Note: these thoughts are mine and the photo is in the public domain.