Over the holiday period, the Guardian leader column is looking ahead at the themes of 2026. Today we look at the impact of devolution on growing volatility of party political allegiance

Next year will be pivotal in British politics, and 7 May will be the point around which things pivot. Elections to local councils, the Scottish parliament and the Welsh Senedd will give millions of voters across the UK a chance to express party preferences. Their verdicts could imperil Labour and Conservative leaders. In Wales, Labour might be sent into opposition for the first time since devolution. Plaid Cymru and Reform UK are set to make substantial gains. At Holyrood, the Scottish National party (SNP) is on course for a majority. That would be an extraordinary defiance of political gravity for a party weighed down by nearly two decades of incumbency.

In England, both Labour and the Tories risk losing scores of councillors as their vote shares are gobbled up by the Liberal Democrats, Reform UK and the Greens. Those results will be taken as evidence that Sir Keir Starmer and Kemi Badenoch are failing as leaders. But it would be a mistake to filter the results only through that lens. The fragmentation of national allegiances began much longer ago.

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Our 20 favourite pieces of in-depth reporting, essays and profiles from the year

Victor Pelevin made his name in 90s Russia with scathing satires of authoritarianism. But while his literary peers have faced censorship and fled the country, he still sells millions. Has he become a Kremlin apologist?

Australian researchers think the skeleton found in South Africa is not the same species as two found in the same South Africa cave system

Little Foot, one of the world’s most complete hominin fossils, may be a new species of human ancestor, according to research that raises questions about our evolutionary past.

Publicly unveiled in 2017, Little Foot is the most complete Australopithecus skeleton ever found. The foot bones that lend the fossil its name were first discovered in South Africa 1994, leading to a painstaking excavation over 20 years in the Sterkfontein cave system.

Groundbreaking find makes compelling case that humans were lighting fires much earlier than originally believed

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It is known that humans used natural fire more than 1m years ago, but until now the earliest unambiguous example of humans lighting fires came from a site in northern France dating from 50,000 years ago.

A fin whale washed ashore in Anchorage and was left there for months. Then a self-described ‘wacko’ museum director made a plan

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