Morning mail: Biden's call for unity, subalpine forests struggle, Hottest 100 guide

Thursday: Joe Biden is sworn in as US president, saying democracy has prevailed'. Plus: a father's struggle to challenge police brutality

Good morning, this is Richard Parkin bringing you the main stories and must-reads on Thursday 21 January. The world's media will be largely fixed upon Washington DC today after Joe Biden was sworn in as the 46th president of the United States. And, closer to home, the productivity commission has come under fire for recommending that the Australian government should pursue unpaid student loans from people who have died.

Joe Biden has called for unity during his first speech as president, acknowledging the nation's historic moment of crisis and challenge". Kamala Harris became the first woman in history to enter the office of vice president, with the former Californian attorney general expected to play a crucial role as the deciding vote in a Senate that is split 50-50 along party lines. European leaders have expressed relief at a new dawn in America", with European Commission president Ursula von der Leyen saying the continent once again has a friend in the White House". Biden's inauguration could also spell good news for Australia, with advisers suggesting he will look to renew a really strong relationship" with its historic ally.