The Period Beginning with the Cambrian and Up to the Present

question 73

Short Answer

The period beginning with the Cambrian and up to the present represents the _______ eon, which spans approximately 500 million years.

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Definitions:

Low Survival Rate

Refers to a situation where a small percentage of members of a group or species continue to live under certain conditions.

Directional Selection

Directional selection refers to a process in evolutionary biology where an extreme phenotype is favored over other phenotypes, causing the allele frequency to shift over time in the direction of that phenotype.

Hawaiian Honeycreepers

A group of small, colorful birds native to Hawaii, known for their diverse beak shapes and sizes, adapted to different feeding habits and ecological niches.

Ecological Niches

The role and position a species occupies in its environment, including all interactions with biotic and abiotic factors.