Biodiversity Change Caused by Genetic Techniques
San Diego Zoo Wildlife Alliance's 'Frozen Zoo' has stored living cell cultures from 10,900+ species since 1976. In 2018, the last 2 northern white rhinoceroses were female (Najin and Fatu); survival of the sub-species now depends on combining banked sperm with induced pluripotent stem cells from banked skin cells to produce synthetic gametes. Hildebrandt et al. announced this pathway in 2021 Nature Communications. Genetic technologies can work against extinction, or inadvertently accelerate it.
Practise this lesson
Four printable worksheets that build from the foundations up to exam-style questions, start at whatever level suits you.
How genetic techniques affect biodiversity, at genetic, species and ecosystem levels.
One student says, "If biotechnology helps a crop survive better, then it must increase biodiversity." Another says, "Biotechnology always reduces biodiversity because it interferes with nature."
Write why both statements are too absolute. Then explain why biodiversity effects should be judged across more than one level.
Know
- Biotechnology can increase, decrease or have mixed effects on biodiversity.
- Biodiversity should be evaluated at genetic, species and ecosystem levels.
- Uniformity and conservation support can both be outcomes of genetic techniques.
Understand
- Improved productivity is not the same thing as improved biodiversity.
- Reduced genetic variation can increase vulnerability even if short-term output improves.
- Some technologies may support threatened populations or conservation planning.
Apply
- Evaluate biotechnology effects with balanced language.
- Compare monoculture risk with conservation-genetics benefit.
- Write biodiversity-focused rather than production-only responses.
Core Content
Three levels · one yes/no answer is too simple
The San Diego Zoo Wildlife Alliance's 'Frozen Zoo' bank, established in 1976, stores living cell cultures from 10,900+ species, including northern white rhinoceros skin cells. At the genetic level, this cryopreservation approach prevents the complete loss of alleles from a lineage. But if synthetic gametes produced from those cells produce offspring that survive, those individuals represent a genetically bottlenecked population: maximum diversity preserved in a freezer still means minimum diversity in any living population that descends from 2 females and banked sperm from a handful of males.
Genetic level
Ask whether variation within populations is being increased, maintained or reduced.
Species level
Ask whether species persistence, abundance or range is being supported or undermined.
Ecosystem level
Ask whether communities, habitats and interactions are becoming more stable, less stable or altered in uncertain ways.
This framework prevents superficial answers. The same genetic technique may raise productivity in one crop system but reduce genetic diversity in that crop, while also changing ecological relationships in the surrounding environment.
Biotechnology can affect biodiversity at genetic, species and ecosystem levels, a technique can help one level while harming another, so evaluation must ask whether genetic, species or ecosystem diversity is increased, maintained or reduced.
Pause, copy the highlighted framework into your book before moving on.
Biodiversity should be considered at which levels?
Possible negative effects · uniformity and narrow selection
We just saw that biodiversity has three distinct levels that must each be evaluated. That raises a question: how does biotechnology specifically reduce biodiversity? This card answers it → monoculture and genetic uniformity risks.
Genetic uniformity
- Widespread use of a few successful varieties can reduce genetic diversity.
- Lower variation may increase vulnerability to disease or environmental change.
Monoculture systems
- High productivity may come with lower crop diversity.
- Associated ecosystems may also become less varied or more vulnerable.
Ecological uncertainty
- Some changes may affect non-target species or ecological interactions.
- Impacts can be difficult to predict perfectly in complex ecosystems.
Biotechnology may reduce biodiversity by increasing genetic uniformity through reliance on a few successful varieties, lower variation raises vulnerability to disease or environmental change and can make associated ecosystems more fragile.
Add the highlighted point to your notes before the check below.
Why can widespread use of one crop genotype reduce biodiversity?
Possible positive effects · conservation genetics
We just saw that biotechnology can reduce biodiversity through monoculture effects. That raises a question: can biotechnology also support or improve biodiversity? This card answers it → conservation genetics as a positive application.
Biotechnology does not only threaten biodiversity. Conservation genetics, population monitoring, breeding management and disease screening can help preserve threatened populations, identify low-diversity populations, or guide strategies that reduce inbreeding and improve long-term survival.
Conservation support
- Genetic analysis can identify populations at risk.
- Management can target inbreeding problems or low diversity.
Disease management
- Genetic tools can help protect vulnerable species or breeding programs.
- May support survival of threatened populations.
More informed planning
- Data from biotechnology can improve conservation decisions.
- Better decisions may support biodiversity across multiple levels.
Biotechnology can also support biodiversity through conservation genetics, genetic analysis identifies at-risk or low-diversity populations, tools can manage inbreeding and protect breeding programs, and biotech data improves conservation planning decisions.
Pause, write the highlighted principle into your book.
Which example best shows a positive biodiversity role of biotechnology?
Balanced judgement · the conditional conclusion
We just saw that conservation genetics can support biodiversity. That raises a question: how should a balanced evaluation present these mixed effects? This card answers it → conditional, level-specific evaluation language.
A strong HSC evaluation avoids slogans. A technology may increase food production and reduce one pressure on land use, but still narrow crop genetic diversity. A conservation technology may help one species, but require continued human management or create trade-offs elsewhere. The correct conclusion is often conditional.
Balanced language
- "May increase" or "may reduce" biodiversity depending on the context.
- "Positive at one level, negative at another" is often the strongest answer.
- Avoid "always" and "never" claims.
That kind of judgement prepares students for the final biotechnology synthesis in the next lesson.
Most real biodiversity outcomes of biotechnology are mixed, not purely positive or negative, the strongest HSC answers use conditional language ("may increase/reduce depending on context") and identify which level of biodiversity is affected and how.
Pause, copy the highlighted principle into your notes before continuing.
Growing one genetically similar crop on a huge scale is called _____.
Activities
Level Check
For each statement, identify whether the biodiversity effect is mainly at the genetic, species or ecosystem level.
- A crop system relies on one dominant genotype.
- A conservation program prevents extinction of a threatened species.
- A change in agricultural practice affects surrounding ecological interactions.
Mixed Judgement
Write one short paragraph explaining how a biotechnology could improve one aspect of biodiversity while reducing another.
Core biological claim
- Genetic techniques can have positive, negative or mixed effects on biodiversity.
Mechanism or process
- They may reduce diversity through uniformity and monoculture, or support biodiversity through conservation genetics and informed management.
Common exam error
- Equating improved productivity with increased biodiversity.
Evaluative sentence starter
- "Although the genetic technique may improve productivity or conservation in one context, its biodiversity effect depends on whether genetic, species and ecosystem diversity are maintained or reduced."
A fresh set drawn from this lesson's question bank, feedback shown immediately. +5 XP per correct · +25 XP all correct
Pick your answer, then rate your confidence, that tells the system what to drill next.
UnderstandBand 3(3 marks) 1. Explain how biotechnology can reduce biodiversity in some agricultural systems.
AnalyseBand 4(4 marks) 2. Compare a negative biodiversity effect and a positive biodiversity effect of genetic techniques.
EvaluateBand 5–6(5 marks) 3. Evaluate the claim: If a biotechnology helps one species survive, then it must improve biodiversity overall.
Show all answers
Multiple choice
MC answers and full explanations are shown inline as you complete each question. Use the retry button to attempt a fresh set from the lesson bank.
Activity 1, Level check
1. Mainly genetic level.
2. Mainly species level.
3. Mainly ecosystem level.
Activity 2, Mixed judgement
A strong answer would explain that a biotechnology might improve species survival or crop productivity in one context, while simultaneously reducing genetic diversity or altering ecosystem interactions in another. The key is to make the trade-off explicit.
Short Answer Model Responses
Q1 (3 marks): Biotechnology can reduce biodiversity when it promotes widespread use of a few genetically similar varieties [1]. This lowers genetic diversity within crop populations [1]. Reduced diversity can increase vulnerability to disease or environmental change [1].
Q2 (4 marks): A negative biodiversity effect is reduced genetic diversity through monoculture or heavy reliance on a few successful genotypes [1]. A positive biodiversity effect is the use of conservation genetics to help manage threatened populations [1]. The comparison is that one reduces variation, while the other may help preserve or manage it [1]. Therefore genetic techniques can push biodiversity in different directions depending on how they are used [1].
Q3 (5 marks): The claim is too simple because helping one species survive does not automatically improve biodiversity overall [1]. It may be positive at species level if a threatened population is supported [1]. However, the same intervention may have mixed or uncertain effects at genetic or ecosystem level [1]. For example, it might reduce genetic diversity or alter ecological interactions [1]. Therefore biodiversity should be judged across multiple levels rather than assumed to improve overall from one apparent success [1].
Biodiversity levels
Genetic, species and ecosystem.
Negative effect
Uniformity can reduce genetic diversity and resilience.
Positive effect
Conservation genetics can help manage threatened populations.
Exam trap
Confusing productivity gain with biodiversity gain.
Rapid-fire questions on biodiversity levels, monoculture risk and conservation genetics. Beat the boss to bank a tier, gold (perfect + fast), silver (80%+), or bronze (cleared).
Return to the northern white rhinoceros case from the San Diego Zoo Wildlife Alliance's 'Frozen Zoo' (1976-present) and Hildebrandt et al.'s 2021 Nature Communications paper. You should now be able to explain that the 'Frozen Zoo' preserves genetic diversity at the allele level for 10,900+ species, a clear biodiversity benefit. However, any northern white rhino population produced by synthetic gametes from Najin, Fatu, and banked males would have extremely low genetic diversity, increasing inbreeding risk, a biodiversity cost at the population level. Biotechnology effects on biodiversity are always multi-dimensional.