Donald Trump shakes up campaign (again) Republican hires Breitbart chief; California wildfires drive 80,000 from homes; and the Guardian heads deep underwater Donald Trump greets the crowd in Altoona, Pennsylvania. Photograph: Evan Vucci/AP Edward Helmore in New York Donald Trump shakes up campaign Donald Trump has hired Stephen Bannon of the conservative website Breitbart News as campaign CEO and promoted pollster Kellyanne Conway to campaign manager in his latest campaign shakeup. The moves represent a demotion for the Republican nominee's current campaign chairman, Paul Manafort, who has presided over a period of polling declines since taking control in June. Yesterday, the Guardian looked at how Manafort got a strongman elected in Ukraine. Trump said his new hires were "big people". "I've known both of them for a long time. They're terrific people, they're winners, they're champs, and we need to win it." Trump tweeted the changes did not represent a "pivot" in his approach; he also denied reports that he is being advised by ex-Fox News chief Roger Ailes. Donald Trump appoints Breitbart chief in shakeup that demotes Paul Manafort California wildfire forces evacuation of 80,000 An intense wildfire fanned by strong winds and 100F (37C) temperatures is tearing through rural communities outside Los Angeles, unleashing fire tornados and forcing the evacuation of more than 80,000 people. The so-called Blue Cut fire is 60 miles east of LA, and has already scorched 9,000 acres. "There is imminent threat to public safety, rail traffic and structures," said California's governor, Jerry Brown. He said an estimated 34,500 homes and 82,640 people were being affected by the evacuation warnings. Blue Cut fire scorches 9,000 acres and forces evacuation of 80,000 in California Trip to the bottom The largest migration on Earth is very rarely seen by human eyes, yet it happens every day. Billions of marine creatures ascend from as far as 2km below the surface of the water to the upper reaches of the ocean at night, only to then float back down once the sun rises. This huge movement of organisms – ranging from tiny cockatoo squids to microscopic crustaceans, shifting for food or favourable temperatures – was little known to science until relatively recently. "The deeper we go, the less we know," said Nick Schizas, a marine biologist at the University of Puerto Rico. Oliver Milman takes a trip to Bermuda to ride to the bottom of the sea in a (very hot) submersible. The deep ocean: plunging to new depths to discover the largest migration on earth Biles sweeps the floor, and a boxer claims corruption As the astonishing Simone Biles won her fourth Rio gold, on the floor exercises, incendiary claims of corruption were being levelled at Olympic boxing after Irish world champion Michael Conlan accused Aiba, the amateur sport's governing body, of corruption "from the core right to the top" after losing in the bantamweight quarter-finals to the Russian Vladimir Nikitin. "They're f**king cheats," he shouted into the ringside microphone. And the father of US boxer Gary Antuanne Russell claimed the fix was in when he lost his fight to Uzbekistan's Fazliddin Gaibnazarov. "He got robbed," shouted his father, Gary Russell Sr. An unnamed official added his opinion: "As predicted, the corruption is alive and well and the decisions speak for themselves." Meanwhile, Brazil knocked the US out of women's beach volleyball and China bemoaned its disappointing medal tally while Britain celebrates its surprisingly robust haul. Here is our daily Rio briefing for Day 12. Olympic boxing corruption alive and well, says official as rows continue Putin 'conflicted' over Trump Last December, Russian president Vladimir Putin described Donald Trump as "a colourful and talented man". In June, he said: "Mr Trump has declared that he's ready for the full restoration of Russian-American relations. Is there anything bad there? We all welcome this, don't you?" Despite reports of potential links between the two men, these are the only public comments Putin has made on Trump. So, is Putin hatching a cunning plan to put Trump in the White House? Shaun Walker in Moscow reports. Putin's praise for Trump may mask 'conflicted' feelings, Kremlin watchers say Death penalty: a subject no one wants to touch in 2016 Neither presidential candidate is keen to address the topic, despite waning public support for it. Donald Trump has voiced support for capital punishment on at least two occasions; Hillary Clinton only talks about capital punishment when pressed, and then clumsily. Unlike most of her own party, Clinton supports execution in the case of terrorists. The best policy may be silence. "Why bring it up if it's going to stir the pot, if you don't have to?" says Sherry Bebitch Jeffe, professor of public policy at the University of Southern California. Politics and the death penalty: for Clinton and Trump, safest stance may be silence Ford to mass-produce driverless car The auto manufacturer has announced it will produce a fleet of driverless cars for ride-sharing services, such as Uber and Lyft, by 2021. Mark Fields, Ford's president and chief executive, said the next decade would be "defined by automation of the automobile" and the switch to driverless travel would affect society as much as the introduction of the assembly line did a century ago. The company said its new cars would be fully automated. Ford to build 'high volume' of driverless cars for ride-sharing services Film director's rape charge complicates hotly anticipated release Nate Parker, the director of the fall's most anticipated film, the slavery drama The Birth of a Nation, may have clouded the release of his film by electing to discuss the circumstances in which he was tried for rape while at college in 1999. Parker granted two interviews with the Hollywood trade papers in which he described how he and Jean Celestin, a fellow student at Penn State University, were charged with raping a female student while she was unconscious. Parker was acquitted of the charges in 2001; Celestin was initially found guilty and later granted a new trial that was never held. The Birth of a Nation's reception compromised by director's rape trial In case you missed it … With fashion's marketing season approaching again, Kate Baron casts an eye over the highlights of fashion's long association with pop music courtesy of her new book, Fashion + Music. Stylist Judy Blame describes the birth of pop music's inimitable cyber pixie – Björk. "She wanted to look like a little animal, so I just yanked that little furry jumper off Martin's [Martin Margiela] rail. Then [the French make-up artist] Topolino came in and put those two sequins under her eyes and that was it – the full stop!" And so it goes with fashion. Fashion's greatest pop hits – from Gaga's meat dress to Grace Jones's Armani suit Manage your emails | Unsubscribe | Trouble viewing? You are receiving this email because you are a subscriber to Guardian US Briefing. 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