Cambrian explosion

Question 1

Some think steep rise in … … sparked change, others say it sprang from development of some key … …, such as …, or the evolution of…

Answer 1

oxygen levels, evolutionary innovation, vision (evolution of the eye), predation

Question 2

Potentially, increase in … enabled the emergence of … which had higher … …

Answer 2

O2, predators, metabolic rate

Question 3

The evolution of predation would set of an … … …, and increased … … which could have driven rapid …, and niche filling

Answer 3

evolutionary arms race, selection pressures, diversification

Question 4

There is evidence in … minerals in rocks formed during the Cambrian period that oxygen concentrations significantly rose at the start of the Cambrian

Answer 4

metal (solubility)

Question 5

However this was recently contested, with new evidence suggesting…

Answer 5

no statistically significant increase in the proportion of oxic to anoxic water at the boundary between the Ediacaran and Cambrian

Question 6

Suggested that oxygen could already have been abundant enough … … the cambrian explosion

Answer 6

long before

Question 7

Evidence that conditions with higher oxygen do house more … and complex … …

Answer 7

diversity, food webs

Question 8

The need to avoid … may have driven animals into the … …, where … levels were higher so they had the energy to …

Answer 8

predators, water column, oxygen, swim