Ecological niches: resources, conditions and interactions
הוצג| English | משמעות |
|---|---|
| ecological niche/ˌekəˈlɒdʒɪkl niːʃ/ | נישה אקולוגית |
| resource partitioning/rɪˈzɔːs pɑːˈtɪʃənɪŋ/ | חלוקת משאבים |
What would explain this observation?
- Two species can share a habitat while using different resources or using the same resource at different times. A niche describes more than a location.
Build the model
- An ecological niche 生态位 includes how an organism uses resources, responds to conditions and interacts with other organisms.
- A fundamental niche describes potential conditions without restrictive biotic interactions in the model; a realized niche describes the conditions occupied when those interactions operate.
- Competition can restrict resource use or distribution.
- ecological niche: The resource use, conditions and interactions associated with an organism’s role.
- resource partitioning 资源分割: Differences in resource use that can reduce overlap among organisms.
What evidence concerns a niche rather than only a habitat location?
רמת קושי 1/5 · 100 מטבעות + בונוס קטן בהשלמה הראשונה היום
A niche is the species' role: what it eats, the conditions it tolerates and how it interacts. Recorded resource use with conditions addresses that; a map coordinate or a site name is only a location.
Match each technical term to its precise meaning.
רמת קושי 2/5 · 140 מטבעות + בונוס קטן בהשלמה הראשונה היום
Use the definitions to distinguish related quantities and processes.
Choose evidence that can test it
- Separate a habitat observation from a causal claim about a niche boundary.
- Absence from a site can reflect dispersal, detection, abiotic conditions or interactions.
- Resource partitioning can reduce overlap, but an observational difference alone does not prove that competition caused it.
- Compare alternative explanations and the timescale of evidence.
In the lab: Use permitted field observations or an attributed dataset. Record species identification confidence, resource category, time, abiotic conditions and sampling effort. Repeat observations at several locations rather than choosing only patches that fit the hypothesis. Non-destructive comparisons or approved models should be used instead of removing native species or introducing competitors.
Which two habits make the investigation or model in this case more defensible?
רמת קושי 2/5 · 140 מטבעות + בונוס קטן בהשלמה הראשונה היום
Stating the conditions and assumptions lets others repeat the work exactly, and recording the supporting evidence lets them check the conclusion. Hiding disagreeing results removes the evidence that could challenge a wrong conclusion, and one measurement can never establish a wider claim.
Work from known quantities
- Known: fictional birds A use resource categories in counts 18, 9 and 3 out of 30 observations; birds B use 3, 9 and 18.
- Their shared middle category is 30% for each, but the preferred categories differ.
- This is evidence of different observed resource use.
- It does not alone establish their full niches or demonstrate the cause of the difference.
Your turn: A species uses one resource in 12 of 40 feeding observations. Calculate the observed percentage.
A species uses one resource in 12 of 40 feeding observations. Calculate the observed percentage.
רמת קושי 2/5 · 140 מטבעות + בונוס קטן בהשלמה הראשונה היום
The result is 30 %. Known: 12 of 40 feeding observations use the resource. Use percentage = count / total x 100. Percentage = 12/40 x 100 = 30%. Observed use in one survey does not by itself define the whole niche.
Check the conclusion and its limits
- A niche is not identical to a trophic level or a habitat.
- A realized niche is a context-dependent model, and an incomplete survey cannot establish every tolerance limit or competitive interaction.
Not true: Two species living in the same habitat necessarily have identical ecological niches. Species sharing a habitat can partition it - different foods, times or microsites - so identical location does not mean identical niches. Competition actually pushes coexisting species apart in their resource use.
- An ecological niche includes how an organism uses resources, responds to conditions and interacts with other organisms.
- Separate a habitat observation from a causal claim about a niche boundary.
- Watch for: A niche is not identical to a trophic level or a habitat.
Write from 40 percent of feeding observations
- A species uses one resource in 14 of 35 feeding observations.
- Find the percentage. Absence from a site is not by itself a niche boundary.
Species sharing a habitat can partition it - different foods, times or microsites - so identical location does not mean identical niches.
רמת קושי 1/5 · 100 מטבעות + בונוס קטן בהשלמה הראשונה היום
True. Species sharing a habitat can partition it - different foods, times or microsites - so identical location does not mean identical niches. Competition actually pushes coexisting species apart in their resource use.
The resource use, conditions and interactions associated with an organism’s role: write the technical term.
רמת קושי 1/5 · 100 מטבעות + בונוס קטן בהשלמה הראשונה היום
ecological niche means The resource use, conditions and interactions associated with an organism’s role.
A species uses one resource in 14 of 35 feeding observations. What percentage is that, and why is absence from a site not automatically a niche boundary?
14 out of 35 is 0.40, which is 40 percent of these observations.
What percentage of the observations used that resource?
רמת קושי 1/5 · 100 מטבעות + בונוס קטן בהשלמה הראשונה היום
14 divided by 35 is 0.40, which is 40 percent.