Conservation of biodiversity

The **variety of life** in an area — including **species, habitat and genetic** diversity.

The **number of different species** present in a community.

The ability of an ecosystem to **keep functioning and recover** after a disturbance.

**Species** diversity, **habitat** diversity and **genetic** diversity.

Species' roles **overlap**, so if one species is lost **another can cover its role** — the ecosystem keeps working.

It provides **food and materials**, **medicines**, and **ecosystem services** (e.g. pollination, water cleaning).

Free 'work' an ecosystem does for us — e.g. **bees pollinating crops** or wetlands cleaning water.

It is **irreversible** — a species' genes and its ecological role are gone **forever**.

**Habitat destruction**, **overexploitation** and **pollution** (also invasive species and climate change).

The current **rapid, human-driven** loss of species, happening far faster than the natural background rate.

Link **more species** to a **benefit** — usually greater **stability / resilience** or more **ecosystem services**.

You must **link** the extra species to a **consequence** (stability, services); the variety alone is not the mark.

The **permanent loss** of a species when its **very last member dies**.

**Habitat loss, overexploitation, pollution, invasive species, climate change** (memory hook: HIPPO).

**Habitat loss** — clearing a habitat removes the home of **every** species that depends on it at once.

Destruction or fragmentation of the **natural place a species lives** (e.g. deforestation, draining wetlands).

Harvesting or hunting a species **faster than it can reproduce**, so its population crashes.

A **non-native** species, introduced by humans, that spreads and **harms native species** by competing with, eating or infecting them.

Native island species often have **no defences** against a brand-new predator or competitor.

Harmful substances such as **pesticides or plastic** added to air, water or soil **poison or kill** wildlife.

Human-driven warming **shifts conditions faster than species can adapt** (e.g. coral bleaching as the sea warms).

**Extinction** = one whole species lost forever; **biodiversity loss** = the **wider fall** in variety, including shrinking populations.

**Named impacts with reasoning** (a direct and a knock-on effect) — not just 'it is bad'.

Protecting a species **within its natural habitat** (e.g. in a nature reserve or national park).

Protecting a species **outside its natural habitat** (e.g. in a zoo, botanic garden or seed bank).

**Nature reserves / national parks** and **wildlife corridors** that connect them.

The **whole ecosystem** is conserved together, so the species keeps a large population with **high genetic diversity** and behaves naturally.

A protected strip of habitat that **connects two separate reserves** so animals can move between them.

It lets animals **move, interbreed and recolonise** between reserves — keeping populations larger and genetically diverse.

The breaking up of one large habitat into **smaller, separated patches**.

The **harsher conditions** (wind, light, predators, invasive species) found **near the boundary** of a habitat patch compared with its interior.

A **large, rounded** reserve — it has **more sheltered interior** and **less exposed edge**.

It is **almost all edge**, so harsh edge conditions reach every part and few interior species survive.

The wild population stays **large**, so a wide range of alleles is kept (unlike a small captive group).

It conserves the **whole habitat/ecosystem** and lets the species **behave and evolve naturally**, not just survive in captivity.

**Captive breeding** (zoos), **botanic gardens**, and **seed / gene banks**.

Breeding endangered animals **under human care** to raise their numbers, often to **reintroduce** them to the wild.

A cold, dry store of seeds from many species kept as a **long-term genetic back-up**.

Animals breed **safely** (away from predators/poachers) under expert care, so the **population grows**.

They **preserve genetic variety** so a species can recover even if wild populations are lost.

**Releasing** captive-bred individuals back into a (protected) **natural habitat**.

It is **expensive** and holds **small numbers** (inbreeding risk); it also **does not protect the habitat**.

They may **lack survival skills** learned in the wild, so they can struggle to find food or avoid predators.

It keeps a species alive when its **wild habitat is too damaged**, but it does not protect that habitat — so it works **best alongside in situ**.

**In situ protects the habitat** (the species stays in the wild); **ex situ does not** (the species is held off-site).

Restoring the **natural processes** of a degraded ecosystem so it becomes **self-sustaining**, often by reintroducing a **keystone species**.

A species whose effect on its ecosystem is **far larger than its numbers** suggest (e.g. a top predator or a beaver).

An ecosystem that has been **damaged** so it works less well (e.g. a cleared forest or drained wetland).

Reintroducing a **keystone species** to restart natural processes across the ecosystem.

Restore natural **water flow** (re-flooding), re-establish natural **grazing**, let **native plants** return, or reconnect habitats with **corridors**.

Conservation protects species and often needs **ongoing management**; rewilding restores **natural processes** so the ecosystem **manages itself**.

Its activity (e.g. damming or predation) restarts a **chain** of natural processes that many other species depend on.

**Beavers** — they build dams that restore water flow and create wetland that supports many species.

Repairing a **damaged** ecosystem so its **natural processes** and **biodiversity** recover.

By restoring natural processes in a **degraded** ecosystem, it **reverses** damage so more species can return.

Any two of: **grazing**, **predation**, **flooding/water flow**, **seed dispersal**.

Restore a **natural process** (not just add a species) — e.g. re-flooding or letting native plants return.

**Evolutionarily Distinct and Globally Endangered**.

To **prioritise** which species to conserve — choosing those that are both distinct and endangered when resources are limited.

Having **very few close living relatives** — a unique, long branch on the tree of life carrying unique evolutionary history.

At **high risk of extinction worldwide** (e.g. a very small or fast-falling population).

A species that is **both** highly evolutionarily distinct **and** globally endangered — so it is high priority for conservation.

There are **more endangered species than money, land and time** to save them all, so choices must be made.

**No** — it is distinct but not at risk, so it is not urgent.

**No (lower)** — its loss is a smaller loss to the tree of life because similar species remain.

It removes a **unique branch of the tree of life and unique genes** that **no other species can replace**.

**Protecting species and habitats** so that biodiversity is maintained for the future.

It must be **evolutionarily distinct AND globally endangered** — high on both, not just one.