"Several years ago I noticed that people kept saying that giant squids reached 60 feet in length, which is amazingly long," Craig McClain, the assistant director of the National Evolutionary Synthesis Center in Durham, N.C., and the study's lead author, said in a statement. "When I started actually looking at the data, I found that that estimate was actually quite unrealistic."
Along with a host of students, he fact-checked commonly cited sizes with historical data, scientific literature and specimens (both in museum and available for sale on the Internet).
Why the inaccuracy? Some of these sea monsters are rarely seen or captured. Others, like the giant squid, are fragile -- and might stretch after death.
But the true measurements are still far from unimpressive, as you can see.
One thing the researchers noticed is just how variable some species can be. Some species can have remarkably different sizes throughout their life cycle, and some of that variation is based on environment. In some, for example, an abundance of food during growth will mean a massive size increase over starved members of the same species.
But while humans are likely to admire the biggest member of a species (for no reason other than sheer awe), being the largest of an already large group isn't always a good thing. For some species -- as in humans -- extreme size can lead to health problems and early death.
Want more information on the giants of the sea? Check out the live-streamed dissection of a colossal squid here.