How large was the Smilodon?
Smilodon
Overall, Smilodon was more robustly built than any extant cat, with particularly well-developed forelimbs and exceptionally long upper canine teeth. Its jaw had a bigger gape than that of modern cats, and its upper canines were slender and fragile, being adapted for precision killing. S.gracilis was the smallest species at 55 to 100kg (120 to 220lb) in weight. S.fatalis had a weight of 160 to 280kg (350 to 620lb) and height of 100cm (39in). Both of these species are mainly known from North America, but remains from South America have also been attributed to them. S.populator from South America was the largest species, at 220 to 400kg (490 to 880lb) in weight and 120cm (47in) in height, and was among the largest known felids. The coat pattern of Smilodon is unknown, but it has been artistically restored with plain or spotted patterns.
Mastodon
Modern reconstructions based on partial and skeletal remains reveal that mastodons were very similar in appearance to elephants and, to a lesser degree, mammoths, though not closely related to either one. Compared to mammoths, mastodons had shorter legs, a longer body and were more heavily muscled, a build similar to that of the current Asian elephants. The average body size of the species "M. americanum" was around in height at the shoulders, corresponding to a large female or a small male; large males were up to in height. Among the largest male specimens, the 35-year-old AMNH 9950 was tall and weighed , while another was tall and weighed . 