How the return of just 66 wolves rejuvenated Yellowstone’s entire ecosystem

Yellowstone’s reintroduction of wolves in 1995 is one of the best-known instances of a trophic cascade – a single change in a food chain that transforms an entire ecosystem. The return of the wolves rejuvenated wildlife in the park from top to bottom, even changing the area’s physical geography as native animals and plants reasserted themselves. Narrated by George Monbiot, How Wolves Change Rivers chronicles how Yellowstone’s extraordinary success in rewilding stems from a decrease in invasive and overpopulated species such as coyote and deer thanks to just 66 wolves returning after a 70-year absence from the park.

Evolution is not only about competition: the cellular origins of a very big idea

If the competitive nature of existence ever gets you down, you might want to consider one leading theory of how complex life came to emerge in the first place. The endosymbiotic theory of mitochondrial origin (also known as symbiogenesis) is one of the leading theories for the development of eukaryotes – the nucleus-containing cells that are the building blocks of all multicellular organisms. According to the theory, narrated here by the biologist Rob Lue of Harvard University, it was a symbiotic partnership between two primitive cells that allowed them to thrive, develop organelles for specialised tasks, and eventually give rise to complex new lifeforms. In other words, cooperation was key – and it remains so today.

Heavy is the 11-year-old head that wears the crown at an Argentinian beauty pageant

‘It gets heavier and heavier by the minute. Until the callus forms. Right, Memi?’

With an unflinching focus, the Argentinian filmmaker Manuel Abramovich traces the boredom, annoyance and pain – and perhaps confusion – that pass across the face of María Emilia Frocalassi (‘Memi’) as her mother fits her with a lavish, heavy headpiece. The 11-year-old has recently won a beauty pageant and will be competing in another held as part of carnival celebrations in rural Argentina. Intercutting the pageant preparations with Memi’s tennis and swimming lessons, Abramovich binds the whole spectacle together with a soundtrack of adults relentlessly dispensing directions and expectations. When Memi finally starts to crack, it’s perhaps not just under the weight of her enormous headdress. A winner of dozens of film-festival accolades since its 2013 release, the critically acclaimed short La Reina (The Queen) is a strikingly original and confronting exploration of adolescence, tradition and the dynamics of a mother-daughter relationship.

Our biological past and our technological future play out on a single human face

In this animated self-portrait, the UK artist Emma Allen uses her face as a canvas for a remarkable, millennia-spanning stop-motion. With her features always visible but transformed by the images painted across them, Allen takes us through evolution, from primordial creatures, through large mammals, to humans, before offering a vision of what’s to come – a future in which we transcend the limits of (or perhaps lose touch with) biology. For more from Allen, watch her short video Adam on the experience and neuroscience of depression.

Do the Volgelkop bop: how a newly discovered bird-of-paradise dazzles his mate

Beginning in 2004, the evolutionary biologist Ed Scholes of Cornell University in New York and the US nature photographer Tim Laman embarked on an ambitious project to find and film the 39 then-known members of the birds-of-paradise family that live in remote regions of New Guinea, Australia and nearby islands. Living in largely predator-free habitats have allowed male birds-of-paradise to develop some of the world’s most colourful plumage and elaborate mating displays, making them the favourites of many a David Attenborough nature documentary.

During a 2016 trek to west New Guinea, Laman and Scholes did one better than simply capturing new images of these birds – they discovered a new species. Now known as the Vogelkop superb bird-of-paradise (Lophorina niedda), it was previously considered a subspecies of the Greater superb bird-of-paradise. However, Laman and Scholes’s documentation of the male’s mating dance revealed enough difference in its song, movement and feather display for the Vogelkop superb to be recognised as a distinct species. With its first documented observation dating back to 1930, this video marks the first known time that the male Vogelkop superb has been caught on camera in all its shimmying, brilliant black-and-blue glory.