The first organism evolved from which of the following habitat?

Analyze the question: It asks where the first living organisms came from, meaning the habitat in which life first evolved.

Explain the concept: According to the widely accepted theory of the origin of life (chemical evolution), life began in water. Early Earth had a "primordial soup" of simple organic molecules in the oceans. These molecules joined to form more complex ones, which eventually led to the first simple cells. The fossil record supports this, since the oldest fossils are of simple aquatic prokaryotes (bacteria-like organisms), found in rocks about 3.5 billion years old.

Step-by-step solution:

1. Early Earth's land was harsh. It had intense UV radiation, no ozone layer, and extreme temperatures.
2. Water offered protection, stable conditions, and dissolved chemicals needed for reactions.
3. The first cells therefore appeared in the water (aquatic habitat).
4. Later, organisms moved onto land. Terrestrial, arboreal (tree-living), and desert habitats came much later.

Checking the options:

• A. Terrestrial: land life evolved later.
• B. Arboreal: tree habitats appeared only after land plants evolved.
• C. Aquatic: correct.
• D. Desert: a specialised land habitat that came much later.

**Answer: C. Aquatic.

Exam tip: Remember the order "Water → Land → Trees." Life began in water, moved onto land, and then diversified into specialised habitats. For JAMB, any "first life" or "origin of life" question will almost always point to aquatic environments.