Why are fossils of early life on Earth rarer than fossils of plants and animals from the past few hundred million years?
A) We find fossils in sedimentary layers, and no sediments were deposited until just a few hundred million years ago.
B) Life was far less abundant prior to a few hundred million years ago.
C) Early organisms were microscopic and lacked skeletons and other hard structures that are most likely to be fossilized.
D) Fossils could not form before there was oxygen in the atmosphere.
Question 2
Two stars, Tom and Jerry, have the same spectral type. Tom is luminosity class V and Jerry is luminosity class I. Which star is bigger? Which star is more luminous? Which star has a hotter surface temperature? Explain your answers.
What will be an ideal response?
