New this month Factual error: Kate finds a Graboid fossil and explains that the rock is from the Precambrian era (which ran from about 4.5 billion years ago through about 500 million years ago), thus making them literally the oldest complex life-forms in the history of Earth. Cool idea, but it makes no sense. Life in the Precambrian era was mostly bacterial or simplistic organisms such as sea-sponges and jellyfish late in the era. Something like the Graboids just couldn't have existed, both because they're too complex to have existed in that time-frame and also (and more importantly) because there wouldn't be an adequate food source for them to thrive. Sure, maybe they could have existed during the time of dinosaurs, but that only started about 250 million years ago, way after the end of the Precambrian era.
Factual error: After Grady and Earl wreck their truck, Burt, Earl and Grady have a radio conversation. At one point Grady interrupts Burt's transmission cutting off his voice, but making it appear Burt can hear him. It's not possible to interrupt a transmission while the other person is also transmitting even though they're using repeaters which is why Burt's voice was cut off in mid sentence. The only way you can transmit and receive at the same time is if you're using full duplex. Burt's voice was cut off, therefore they are not using full duplex.