>>To my knowledge, no Therizinosaur skull has ever been found.
>>Just arms, claws, and leg bones.
>>How can anybody tell it was a plant-eater?
Skull has never been found, even Wikipedia says so :0
>>To my knowledge, no Therizinosaur skull has ever been found.
>>Just arms, claws, and leg bones.
>>How can anybody tell it was a plant-eater?
From Wikipedia...
See especially the last paragraph.
Also, plant eaters often have large guts/rib cages for disgesting large amounts of plant matter.
From Wiki:
Though the fossil remains of Therizinosaurus are incomplete, inferences can be made about their physical characteristics based on related therizinosaurids.
Like other members of their family, Therizinosaurus probably had small skulls atop long necks, with bipedal gaits and heavy, deep, broad bodies (as evidenced by the wide pelvis of other therizinosaurids).
Their forelimbs may have reached lengths of up to 2.5 metres (8.2 feet)[1] or even 3.5 metres (11.5 feet) in the largest known specimen.[2] Their hindlimbs ended in four weight-bearing toes, unlike other theropod groups, in which the first toe was reduced to a dewclaw.
In 2010 Gregory S. Paul estimated the maximum size of Therizinosaurus at 10 metres (33 ft) in length and five tonnes in weight.[2] They are the largest therizinosaurs known, and the largest known maniraptorans.[2]
The most distinctive feature of Therizinosaurus was the presence of gigantic claws on each of the three digits of their front limbs. These were common among therizinosaurs but especially large in Therizinosaurus, and while the largest claw specimens are incomplete, they probably reached 0.7–1 metres (2.3–3.3 ft) in length.
The claws are the longest known from any animal.[3] The claws were relatively straight, only gradually tapering into a point, as well as extremely narrow and transversely flattened.[2][4][5][6]
The feeding habits of Therizinosaurus are unknown since no skull material has ever been found that could indicate their diet. However, like other therizinosaurs, they were probably primarily herbivorous.[7]
https://en.m.wikipedia.org/wiki/Therizinosaurus