Floating Futures
Alessandro Gandolfi

Imagine a city where suburbs float on water. Floating homes already exist in coastal communities in places like the Philippines and Vietnam. Now, high-income nations facing dangerous sea-level rise are looking to those examples.

Among them is the Netherlands, where over a quarter of the land is below sea level and around two-thirds of it is at risk of flooding.

This photograph shows floating houses in the IJburg district at the edge of Amsterdam, the largest Dutch city. The image comes from , a new series by photojournalist Alessandro Gandolfi.

The affluent, relatively high-density IJburg community comprises 158 waterside homes, 55 of which are floating. Residents are connected by bridges and roads, and most houses have a boat outside instead of a car.

Simply raising the dykes is no longer enough against the rising waters, Gandolfi writes in his photo essay. “Experts warn that mastering water’s whims is an illusion. The answer, they say, lies in a shift of mindset – the philosophy of meebewegen: not fighting against water, but learning to live with it.”

The homes at IJburg aren’t houseboats or retrofitted vessels like the ones lining Amsterdam’s canals, but architect-designed homes intended to encourage community living. They are built to be sustainable, with rooftop solar panels and careful management of sewage and other waste.

But their biggest difference from other houses will always lie below, in their watery foundations.

Within just a 17-kilometre radius in one Indonesian archipelago, there is an explosion almost every hour as locals practise “bomb fishing”, destroying coral reefs and decimating marine life.

Over 483 days between May 2023 and September 2024, at University College London and his colleagues deployed an acoustic monitoring system at Spermonde Archipelago, south-west of Sulawesi, Indonesia.

As well as being a global coral reef biodiversity hotspot, it is a location where fishers detonate explosives underwater, stunning and killing fish that can then be easily harvested.

“The sound of bomb fishing is so loud that if you’re on a dive it can shake you out of your skin,” says Williams. “You feel it more than you hear it. But if you put your head up on the surface, you likely won’t even see the boat responsible because the sound of bomb fishing travels such a huge distance underwater.”

The recording equipment sat at a depth of 17 metres and was able to detect explosions inside a radius of almost 17 kilometres. The team used AI to analyse their 3650 hours of raw audio. They recorded 3567 explosions, or just over 23 per day while the device was underwater.

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“We have shown the true extent of this practice in a known hotspot for the first time ever, which we hope will drive action to curb this destruction,” says Williams.

One of the biggest issues is that there is an illegal supply chain underpinning the bomb fishing, usually involving the sourcing of fertilisers and fuses or detonators, he says. “In other regions these may be stolen mining explosives or even military explosives.”

Once the fishers have the explosives, enforcement at sea is sparse. “It’s like Whac-A-Mole targeting the bomb fishers. The best approaches should tackle the illegal supply chain that gets the materials needed to make explosives to bomb fishers or sellers of these,” says Williams.

Bomb fishing is a problem across the tropics, and part of the solution is retraining locals in sustainable tourism and reef restoration, he says. “It’s been documented in 34 countries, from South America to the Mediterranean to the East Coast of Africa and South-East Asia.”

, who wasn’t part of the work, is currently studying at the University of Queensland, Australia, and has worked extensively with Indonesian non-governmental organisations in reefs targeted by bomb fishing. He says he wasn’t surprised at the scale of the problem.

“I expected the frequency to be high, but studies regarding bomb fishing are relatively scarce because it is notoriously difficult to quantify,” Gotama says.

He says the new method employed by the researchers might help combat the practice. “If this acoustic method could be replicated elsewhere, it could help with detecting and quantifying blast fishing and help identify hotspots of activity,” says Gotama.

“That could be valuable not only for ecological monitoring, but also for targeting enforcement and evaluating whether management interventions are actually reducing blast fishing.”

Creatures that bridged the gap between reptiles and mammals may have been bearing live young 90 million years earlier than we thought.

One of the hallmarks of all mammals apart from monotremes – echidnas and the platypus – is that they give birth to live young. This “viviparity” contrasts with the “oviparity” seen most other vertebrates, in which females lay eggs that hatch outside their bodies.

One long-standing question has been whether creatures known as cynodonts, which emerged around 260 million years ago during the Permian geological period and are directly ancestral to all mammals, laid eggs or gave birth to live young, as no evidence of their reproduction has been discovered either way.

“Whether mammalian ancestors were oviparous or viviparous has been considered a mystery,” says  at Argentina’s National Scientific and Technical Research Council. “We had no clues on how or when one of the most distinctive traits of the majority of present-day mammals, viviparity, evolved in the mammalian lineage.”

This has now changed, thanks to a chance observation made during a postgraduate class at the University of Buenos Aires in Argentina. The students were examining a fossil of Chiniquodon theotonicus, a cynodont that lived 236 million years ago and was unearthed in the Talampaya National Park in north-western Argentina in 2011. Part of the analysis involved using a microscope to examine thin slices taken from one of the ancient animal’s leg bones. At that point, the class noticed a curious growth line inside the bone.

Gaetano and his colleagues investigated further and eventually concluded that this line, analogous to a tree’s growth ring, recorded the moment that the ancient mammal relative went through a growth spurt after its birth. 

The researchers reconstructed how large the leg bone and the animal itself would have been when the growth line formed. They calculated that the animal would have weighed 1.68 kilograms at that point. When the animal died as a full-grown adult, it was just shy of 12 kilograms.

This gave the researchers a ratio of newborn to adult size in the ancient animal. They then compared this figure to similar ratios obtained from a wide variety of modern animals: 1869 mammals, 2619 non-avian reptiles and 782 birds.

“We were amazed to find that °äłóŸ±ČÔŸ±±çłÜŽÇ»ćŽÇČÔÌęgrouped with extant placental mammals,” says Gaetano.

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Egg-laying animal groups produce young that are far smaller than adults when they hatch, he says.

For example, some species of large birds have newly hatched young that are just 0.002 per cent of adult body mass, whereas placental mammals often give birth to young that are over 20 per cent of the size of their parents.

“Only placental mammals produce relatively large newborns, whereas reptile and bird hatchlings are comparatively very small,” says Gaetano. “Hence, we propose that [the] Chiniquodon theotonicus reproductive strategy was most similar to that of placental mammals.”

 at the University of Bristol in the UK says the findings are convincing.

“Further, as they argue, the apparent absence or rarity of actual eggs of any kind in the Permian and Triassic has always been puzzling – the so-called amniote egg gap,” he says.

 at Macquarie University in Sydney says his gut reaction is to be sceptical of the claim of live birth, as we have only indirect evidence. But he is impressed that, in the absence of any direct fossil evidence, the team is still trying to solve the puzzle.

“We may never get any of the kind of direct evidence that solves the
mystery, for example a fossilised mammalian egg or a fossil mother during
pregnancy,” he says. “So it is kind of cool that they’re taking a different approach to trying to find an answer to that question.”

Three massive black holes have been discovered in a galaxy located in the early universe, 12.5 billion light years away. This has left astronomers surprised that such a complex system could have formed so soon after the big bang.

“This system is in the very, very early universe,” says at the University of Sydney, who wasn’t involved in the discovery. “So, how have we ended up in a situation where these three supermassive black holes have formed and come close together in only a billion years or so since the big bang?”

In December 2024, at the Max Planck Institute for Extraterrestrial Physics in Germany and her colleagues were observing a galaxy known as J0148-4214 through the James Webb Space Telescope when they saw something strange.

At 12.5 billion light years’ distance, the team observed the galaxy as it looked around 1.2 billion years after the big bang, says Übler. “We [also] quickly noticed that the central emission profile of the galaxy had a peculiar shape,” she says.

An analysis revealed two separate regions of high-velocity hydrogen gas in the centre of the galaxy, indicating two so-called accreting black holes that were separated by about 620 light years – a hop, skip and a jump in cosmic terms.

An accreting black hole is a super dense area of space, so compressed that light can’t escape, but that continuously drags in surrounding gas, dust and even stars. Our own galaxy, the Milky Way, has just one massive black hole at the core of its spiral arms.

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“During examination of the whole galaxy, we also noticed another region in the galaxy outskirts with high-velocity hydrogen gas, indicating another, third growing black hole,” says Übler. This one is more than 5500 light years away from the other two.

“We have explored several alternatives ranging from a single black hole to supernovae, shocks, winds and massive stars, but these were all unsatisfactory or incompatible based on our data and previous observations of this system,” she says.

Until now, there was no evidence that massive black hole triplets existed within the first 1.2 billion years of cosmic history, says Übler. “This discovery shows us that processes in the early universe were efficient at bringing massive black holes together,” she says. “It also suggests that black hole merging may have been an additional, fast route for their rapid growth in the early universe.”

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at the University of New South Wales in Sydney says that, based on the information the researchers have presented, she agrees with their conclusion. “The fingerprints look like black holes and the ‘shape’ is best explained with two separate ones,” she says. “The third black hole is better separated, so it is a much cleaner result. Maybe it is falling into the galaxy for the first time, or maybe it has been ejected by interactions with the other two.”

Having three black holes in close vicinity and in a single system suggests there has recently been a merger of separate galactic entities, says Foster. But she says other interpretations may arise in the future, as more observations of the galaxy are made.

Dobie says that a triple black hole system “seems to be the most promising interpretation of the data that they’re seeing”. He also suspects that as more telescopes come online and technology advances, more such galaxies will be found.