so whats your problem with potatoes, huh? you think that just because you're some identical shark scientist you can start relating the steadfast, hardy potato with the GIRLY blushing-red tomato? is that what this is? you with your shrimps and seagull shit having a pop at potatoes?

Giant is relative. That's not giant for a whale shark.

But suppose a hybrid of mako and mackerel shark exhibited this form of gigantism. You would sit up and take notice, and wonder if it's big enough for lasers yet.

How many generations of evolution would it take for it to be noticeably disproportional? Will any of us still be alive?

One.

The article didn't say, but are the hybrids fertile?

Although reading that again I can't help but think they'll get to a point at which they just split into two smaller sharks.

Whoops I missed that. So do biologists consider this genetic pollution desirable or not?

Depends on your standards. This sort of thing is a natural phenomenon, but sometimes it is a result of human action, be it the introduction of invasive species that can breed with the natives, or altering the environment in a way that makes two species' natural ranges overlap. The effect can be the extinction of one or both of the original species, but in some cases can create a whole new species in a single generation. This usually happens in plants.