Deliberate mistake: The decaying tree trunk would have more than likely broken into pieces and/or uprooted from the force exerted by the rope tethered to the pulling Parasaurolophus when Owen wrapped the rope around the trunk to stop the heavy-weight dino, but the trunk held up without even losing a shred of bark. (00:08:36)
Deliberate mistake: After Sam freed Gary from being tied up by the aliens, Gary pulled off the cast he got earlier that day and was able to use his left arm as though it had never been broken. (00:45:43)