The distribution of the large blue butterfly, Phengaris arion, extends across Europe and Asia. It is assessed by the International Union for Conservation of Nature (IUCN) on the Red List™™ as 'Near Threatened' globally and 'Endangered' in Europe. In Europe, P. arion became extinct in the Netherlands in 1964 and in the United Kingdom in 1979. [Figure 6.1] lists the conservation status categories in the IUCN Red List™™. [Figure 6.2] shows P. arion. (a)(i) Explain how IUCN Red List™™ assessments help to conserve biodiversity.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2025). The mark or mark type is shown in brackets.

1. [3] (a)(i) any three from: 1 identify / protect / prioritise, species most at risk ; 2 provide data to / advise, governments / scientists / zoos / industry; 3 so action can be taken to protect a species ; 4 example of conservation action; 5 AVP;
2. [2] (a)(ii) in Europe/west or where, endangered / EN (context must be stated) 1 P. arion less abundant (compared to, Asia/NT) ; 2 more threatened / higher risk of extinction ; 3 AVP;
3. [2] (b)(i) 1 habitat, degradation / change / loss; 2 due to, (change in) farming / development; 3 lack of, food plants / flowers for food;
4. [4] (b)(ii) any four from: 1 prevent extinction / allow survival (of species) ; 2 maintain / increase, biodiversity ; 3 aesthetic/recreational / wellbeing (reasons / benefits); 4 for, scientific interest / research / education; 5 ethical / moral / stewardship (obligation); 6 local cultural significance / save local heritage / ecotourism ; 7 maintain / protect / restore / stability of, food chains / food webs ; 8 pollination / ecosystem, services ;