Examlex
A reflection nebula is caused by:
Darwinian Puzzle
A phenomenon or trait that appears to reduce the fitness of individuals, posing a question as to why it has evolved or been maintained through natural selection.
Chemicals
Substances with distinct molecular compositions that are used in or produced by chemical processes.
Echoes
Reflected sound waves that return to the listener, allowing organisms or devices to locate objects and navigate environments through echolocation.
Hypothesis
A proposed explanation for a phenomenon, made as a starting point for further investigation, which can be tested through experimentation or observation.
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