(part of the lower jaw) containing some teeth (MUCPv-95) to Giganotosaurus. It had been collected by Calvo near Los Candeleros in 1988 (found in 1987), who described it briefly in 1989, while noting it may have belonged to a new theropod taxon. Calvo and Coria found the dentary to be identical to that of the holotype, though 8% larger at 62 cm (24 in). Though the rear part of it is incomplete, they proposed that the skull of the holotype specimen would have been long, and estimated the skull of the larger specimen to have been long, the longest skull of any theropod. In 1999, Calvo referred an incomplete tooth, (MUCPv-52), to Giganotosaurus; this specimen was discovered near Lake Ezequiel Ramos Mexia in 1987 by A. Delgado, and is therefore the first known fossil of the genus. Calvo further suggested that some theropod trackways and isolated tracks (which he made the basis of the ichnotaxon Abelichnus astigarrae in 1991) belonged to Giganotosaurus, based on their large size. The largest tracks are long with a pace of , and the smallest is long with a pace of . The tracks are tridactyl (three-toed) and have large and coarse digits, with prominent claw impressions. Impressions of the digits occupy most of the track-length, and one track has a thin heel. Though the tracks were found in a higher stratigraphic level than the main fossils of Giganotosaurus, they were from the same strata as the single tooth and some sauropod dinosaurs that are also known from the same strata as Giganotosaurus. Continued debate about size In 2001, the physician-scientist Frank Seebacher proposed a new polynomial method of calculating body-mass estimates for dinosaurs (using body-length, depth, and width), and found Giganotosaurus to have weighed (based on the original length estimate). In their 2002 description of the braincase of Giganotosaurus, Coria and Currie gave a length estimate of for the holotype skull, and calculated a weight of by extrapolating from the circumference of the femur-shaft. This resulted in an encephalization quotient (a measure of relative brain size) of 1.9. In 2004, the paleontologist Gerardo V. Mazzetta and colleagues pointed out that though the femur of the Giganotosaurus holotype was larger than that of "Sue", the tibia was shorter at . They found the holotype specimen to have been equal to Tyrannosaurus in size at (marginally smaller than "Sue"), but that the larger dentary might have