Concept17 - Concept 1.3 Biologists explore life across its...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Concept 1.3 Biologists explore life across its great diversity of species Biology can be viewed as having two dimensions: a “vertical” dimension covering the size scale  from atoms to the biosphere and a “horizontal” dimension that stretches across the diversity of  life. The latter includes not only present-day organisms, but also those that have existed  throughout life’s history. Living things show diversity and unity. Life is enormously diverse. Biologists have identified and named about 1.8 million species. This diversity includes 5,200 known species of prokaryotes, 100,000 fungi, 290,000 plants,  50,000 vertebrates, and 1,000,000 insects. Thousands of newly identified species are added each year. Estimates of the total species count range from 10 million to more than 200 million. In the face of this complexity, humans are inclined to categorize diverse items into a smaller 
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.
Ask a homework question - tutors are online