Suppose you could travel back to the Cambrian period in a time machine and carry a full laboratory along with you. To better understand the Cambrian explosion, you might want to _____.
look for multicellular aggregates of
choanoflagellates that were forming
the first animals
look for evidence of complex predator-
prey relationships and measure
oxygen levels in the atmosphere
measure carbon dioxide levels in the
atmosphere and bring traps to collect
terrestrial arthropods
see if animals had gastrula stages
