Lesson 5 of 7 / Climate, biodiversity and disease ecology
Food supply and tropical biodiversity
Why does losing a wild population matter beyond its current use?
In this lesson: Discuss food stress, tropical diversity, biomedicines and crop genetic resources.
About 8 min
The key ideaClimate stress threatens production and erodes biological options for future food resilience and biomedical discovery.
Trace the biological links
Why preserve alternatives before conditions change?
Under drought, B yields 4 while A yields 2 and C yields 3 in this invented trial. Keeping multiple varieties preserves options when conditions change.
| Variety | Well-watered | Drought |
|---|---|---|
| A | 6 | 2 |
| B | 5 | 4 |
| C | 4 | 3 |
These invented values teach genotype-environment comparison, not a recommendation of real varieties. Wild relatives may also hold useful alleles, but transfer and performance need evaluation. Biodiversity supports food webs and provides chemically diverse possibilities for biomedical research; every species is not a proven cure.
Explanation
High temperature can impair crop enzymes, photosynthesis, pollen viability and reproduction, while drought limits water supply and can close stomata. Flooding reduces root oxygen availability; storms can physically destroy crops and infrastructure. Livestock face heat stress, water/feed shortages and changing disease pressure.
Changes in fish distributions and marine productivity can alter catches, while habitat loss can reduce nursery areas. Effects on pests, pollinators and food-chain timing add indirect pressures. Sustainable food supply therefore depends on ecological interactions and resources, not crop growth in isolation.
Tropical ecosystems contain rich species and genetic diversity, often with specialised interactions and limited opportunities to move to cooler conditions. Habitat fragmentation and other stresses can intensify climate effects. Loss of species can remove functions such as pollination and reduce ecosystem resilience.
Wild relatives and local varieties contain alleles that may support future breeding for heat, drought or disease tolerance. Losing genetic diversity narrows those options; no single genotype is guaranteed to perform best under all future conditions.
Biological diversity also contains chemically diverse compounds and mechanisms that can inform biomedical research. The value is a reservoir of possibilities, not a claim that every species contains a proven cure. Conservation protects existing ecological functions and future options whose value may not yet be known.
Step by step
- 1
Identify the production stage
Growth, reproduction, survival or harvest.
- 2
Trace ecosystem dependencies
Include water, pollinators, pests and habitats.
- 3
Explain lost options
Genetic and chemical diversity can support future responses.
Worked example
Work through the evidence
Why might conserving a drought-tolerant wild crop relative help future food security even if it is not eaten now?
One way to explain it
Its genetic variants may be useful in breeding or research to improve crop tolerance under future water stress, preserving options beyond its present direct food value.
Why this answer works
- Useful alleles need evaluation and suitable breeding approaches.
- Conservation does not guarantee immediate transfer or a complete solution.
Is this true? "If a species is not currently a crop or medicine, its loss has no human consequence."
It can support ecological functions and preserve genetic or biochemical options not yet used.