Environmental Filtering Explains Species Similarity
When species live together in the same place and at the same time (co-occur), they often share similar characteristics, like how well they tolerate heat or drought. This happens because the environment acts as a filter.
Environmental filtering means that only species whose traits allow them to survive and reproduce under the specific environmental conditions (like temperature, water availability, etc.) can persist in that habitat. Species that are not well-suited to these conditions are excluded.
Therefore, the species found together are likely those that have passed this environmental filter, leading to them being similar in their tolerances and other traits.
Analyzing Options Related to Species Co-occurrence
- Environmental filtering: This directly explains why co-occurring species are similar. Only individuals adapted to the local conditions (e.g., heat tolerance, drought tolerance) can survive and form a community.
- Limiting similarity: This concept suggests that species competing for the same resources tend to evolve differences to reduce competition, which is the opposite of the observed similarity in traits due to environmental tolerance.
- Divergent evolution: This process leads to species becoming more different over time, usually as they adapt to different environments or niches, not more similar.
- Competitive exclusion: This principle states that two species competing for the exact same limited resources cannot coexist indefinitely; one will eventually eliminate the other. It explains exclusion, not the similarity of coexisting species.
Based on the principle that the environment selects for species with specific suitable traits, environmental filtering is the most likely reason for the observed similarity among co-occurring species.
Important Questions from Abiotic factors
- A researcher carried out an experiment to study how daylength and temperature influence diapause in a moth species. He placed larvae in one of four treatment conditions for 2 weeks, with 30 larvae in each condition. The treatments involved two temperatures ($18\text{ }^\circ\text{C}$ or $27\text{ }^\circ\text{C}$) and two lighting conditions (12h:12h Light:Dark (LD) or complete darkness (DD)). At the end of the experiment, he counted the number of larvae that had entered diapause and those that had not. The data are shown below.Which one or more of the following conclusions can he reasonably make from these findings?
Condition Larvae in diapause Larvae NOT in diapause Treatment 1 $27\text{ }^\circ\text{C}$, 12:12 LD 2 28 Treatment 2 $18\text{ }^\circ\text{C}$, 12:12 LD 7 23 Treatment 3 $27\text{ }^\circ\text{C}$, DD 12 18 Treatment 4 $18\text{ }^\circ\text{C}$, DD 29 1 - Terrestrial plants conduct gas exchange through stomata. Having only few stomata on the leaf surface is a common adaptation to which one of the following conditions?
- Some air-breathing marine vertebrates such as whales, seals and marine turtles possess adaptations for long, deep dives. Which one or more of the following is/are examples of such adaptations?
- Which one or more of the following is/are greenhouse gas(es)?
- You are a plant ecologist studying a plant in the genus Veronica. You notice that, at open rocky sites, Veronica grows as a creeper spreading low to the ground, whereas in grasslands, the stem stands upright. You collect seeds from multiple populations in each habitat type and grow them under uniform conditions in a greenhouse. You find that all the plants grown in the greenhouse have stems that stand upright. Which one or more of the following explanations best support(s) your observations?
