Simplify the following text for a Grade 11 native English-speaking person.
Original: The Snowball Earth hypothesis has been invoked to explain glacial deposits in the Huronian Supergroup of Canada , though the palaeomagnetic evidence that suggests ice sheets at low latitudes is contested .
Simplified: The Snowball Earth hypothesis has been invoked to explain glacial deposits in the Huronian supergroup of Canada . The palaeomagnetic evidence , which suggests ice sheets at low latitudes , is contested .