Answer:
Relative dating is the technique to calculate the age of an ancient materials in comparison to another material's age. Layer A is less older, if layer B lies beneath it. Layer A may be 2.5 to 3 million years old.
Explanation:
Before discovery of radioactive carbon dating method, geologists make use of relative dating method in order to determine the age of rock or fossils. The relative dating procedure often referred to as stratigraphy. Though this procedure is not capable of predict absolute age or dating. In relative dating, is mainly based on the fact that the older rock layers will be deeper in respect to the less older rock layer.
Sea otters are a keystone species. They play an important role in the health and stability of near shore marine ecosystems. They eat sea urchins and other invertebrates that eat vast quantities of giant kelp. ... Providing habitat is one of many services kelp offers to the marine ecosystem.
Answer:
Describe the features that characterized the earliest animals and when they appeared on earth
Explain the significance of the Cambrian period for animal evolution and the changes in animal diversity that took place during that time
Describe some of the unresolved questions surrounding the Cambrian explosion
Discuss the implications of mass animal extinctions that have occurred in evolutionary history
