2–3-cm paired eyes from the early Cambrian (approximately 515 million years old
Anomalocaris
at least 16,000 hexagonally packed ommatidial lenses (in a single eye)
origin of compound eyes deeper down the arthropod stem lineage
evolved before such features as a hardened exoskeleton
processing of visual information would have required
modern) arthropods
brain to be of comparable complexity to
sophisticated nektonic predators with acute vision
within Cambrian communities would have placed considerable selective pressures on prey that would have influenced the ‘arms race’ that began during this important phase in early animal evolution
