In the nature, which of the following is/are most likely to be found surviving on a surface without soil?

1. Fern 2. Lichen 3. Moss 4. Mushroom

Select the correct answer using the code given below.

The correct answer is 2 and 3.

Detailed Explanation:

Primary plant succession often begins on bare, rocky surfaces where soil is completely absent (a process known as primary succession or xerarch succession). Let's evaluate each of the given organisms to understand their ability to survive on a surface without soil:

1. Lichens (2): Lichens are pioneer species in ecological succession on bare rocks. They are a symbiotic association between a fungus and an alga or cyanobacterium. Lichens do not require soil because they get nutrients from the air, rain, and substrate. They secrete organic acids that slowly weather and break down rocks, initiating the process of soil formation.

2. Mosses (3): Mosses are bryophytes that lack true root systems; instead, they have root-like structures called rhizoids used mainly for attachment rather than absorption. Like lichens, mosses often act as pioneer species after lichens have begun building small layers of organic matter. Many species of moss can anchor directly to bare rock, tree bark, or other surfaces without soil, absorbing water and nutrients directly through their leaves and stems from moist air and precipitation.

3. Ferns (1): Ferns are vascular plants that typically require soil containing moisture, organic matter, and developed root systems to anchor themselves and absorb nutrients/water. While some epiphytic ferns grow on trees, in nature, ferns generally appear in later stages of succession after a proper soil layer has formed.

4. Mushrooms (4): Mushrooms are saprophytic fungi that rely on organic matter (decaying plant material, leaf litter, rich soil, or wood) for nutrition. They require organic-rich substrates or decaying soil media to grow and cannot survive on bare soil-less mineral surfaces without host organic material.

Therefore, Lichen (2) and Moss (3) are the most likely organisms to be found surviving on a surface without soil.