AI company Anthropic recently announced that its popular system Claude had identified an unusual family of biological molecules. These molecules were enzymes, a type of protein that speeds up chemical reactions in living organisms.

The new group of enzymes were discovered in bacteriophages – viruses that infect bacteria. Anthropic named them array-associated reverse transcriptases (ARTs).

The finding was presented as an example of AI initiating biological discovery. However, a researcher studying the same enzymes then raised a question: had Claude independently recognised their significance, or could unpublished work shared with the chatbot have influenced its result?

Mario Rodríguez Mestre, a PhD candidate in computational biology at the University of Copenhagen in Denmark, says his team members have been investigating these enzymes, which they call “jumbotrons”, since 2022. According to The Scientist magazine, he shared his dissertation and manuscript drafts with Claude.

Anthropic denies that the model was trained on user transcripts or that its biology team had access to them. Mestre’s concerns and Anthropic’s response raise a question that the available reporting cannot independently resolve. There is no established evidence that his unpublished material was used in the discovery.

Mestre is named among the inventors of a patent for engineered “retrons”, genetic systems that contain a reverse transcriptase enzyme and an associated RNA. The patent also lists reverse transcriptase sequences from jumbo phages, the type of virus involved in Anthropic’s announcement.

Its US application was published in July 2023. This documents earlier work on jumbo-phage reverse transcriptases. But alone it does not establish that the fully system of enzymes described by Anthropic had already been characterised by Mestre’s team.

What was actually found?

Reverse transcriptases are enzymes that copy RNA (a single-stranded molecule that’s essential in most biological functions) into DNA (the double-stranded molecule carrying the instructions for life). Scientists use them in research and diagnostic tests, including some COVID tests.

They also help researchers measure which genes are active in cells, providing clues about cellular function. The enzyme at the centre of Anthropic’s announcement had already been identified by a team of American scientists from Texas A&M University.

What the company claims to have recognised is a larger biological system: the enzyme, a series of repeated DNA sequences, and a possible partner protein. The researchers found that these repeated sequences produce small RNA molecules.

Some of that evidence came from reanalysing data published by another research team in 2022. This illustrates how existing data can reveal new findings while highlighting the importance of crediting the scientists who originally produced them.

Human scientists conducted the laboratory experiments, and important questions remain unanswered. The researchers have not yet shown that this enzyme is active, that it copies the associated RNA molecules into DNA, or what the system does in the virus.

Its resemblance to Crispr, the well-known gene editing tool, has attracted attention. But that resemblance does not mean ARTs can edit genes: this remains a possibility to investigate, rather than a proven application.

How do scientists check an AI discovery?

The Anthropic report about Claude’s findings explains why checking an AI discovery matters. In ten additional search runs, the agents missed the repeat array. Some models could recognise it when given the relevant sequences directly, but recognising a supplied pattern is different to finding it independently.

This limits claims of a consistently autonomous discovery process by Claude. However, it does not show that the biological finding is wrong. The Anthropic report has not yet been peer reviewed.

In my own ongoing research, I use AI to turn biological questions into code and help interpret results. I then develop a documented analysis that other scientists can check and repeat. Researchers should also record the model and instructions used whenever AI is essential to the method.

Before sharing unpublished research with an AI tool, scientists should consult their university’s guidance and seek training on responsible use. Guidelines at the University of Manchester, where I work, advise researchers to protect confidential information, verify sources and keep records of their AI use. A paid subscription does not automatically ensure that research remains private or is excluded from model training.

Anthropic’s personal and business services have different rules. Commercial services exclude inputs and outputs from training by default, though exceptions may apply when users give permission or submit feedback. Their current policies alone cannot tell us what happened to the information Mestre says he shared.

Keeping files on your own computer also does not mean that everything stays there. Claude Science says that datasets and calculations can remain on the researcher’s computer, while the instructions sent to the AI and its replies are processed by Anthropic. Researchers should therefore check what information leaves their computer, how long it is kept and whether it can be used to train models.

Confidential material should only be shared when institutional rules and permissions allow it.

The ART findings raise interesting biological questions, but further experiments are needed to establish what the Claude system does. The debate also highlights a broader issue: how we recognise scientific contributions when AI is involved.

In this instance, credit should acknowledge the researchers who produced the original data, identified the enzymes and uncovered connections between them. Announcements about AI discoveries should explain those human contributions as clearly as they describe what the AI achieved.

Robson Tramontina does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

Awkwardly smiling, a chemist at a waste site is telling me about industrially incinerating corpses. We are crammed into a claustrophobic funnel at the entry point to a rattling shed with high-vis-jacketed workers scurrying to and fro.

The air smells oily and mechanical. With our voices lowered, the conversation is not flowing smoothly. There is a slightly uncomfortable atmosphere, perhaps indicating certain things on our minds that aren’t being said. Passing the waste storage area on my way out, I nervously scan the stacked container rows for the yellow drums which sometimes contain human remains.

You can’t escape the thought of death at these waste incinerators. Potential danger dwells in these spaces through the scorching incineration chambers, uneven steps, machinery flying overhead, and toxic chemicals. Furnace loading points unexpectedly erupt with explosive liquids or a confetti of used bandages and syringes.

Death is also present in the all too real form of anatomical waste. As well as the amputated body parts from living patients, the waste stream includes sealed drums containing heads, torsos and limbs belonging to American body donors.

Parts of corpses travel through industrial incinerators not by accident but by design: they are legal byproducts from biomedical research and development industries and institutions.

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Death seeps into the infrastructural process through abrupt comments, cautious smiles, Excel rows and anonymous yellow drums. It is not known how many anatomical specimens are imported or incinerated in the UK. Britain’s Human Tissue Authority licences over 800 UK-based establishments, who could legally be involved in this process.

But why are they in the UK in the first place?

Many biomedical organisations do not need entire cadavers to conduct their training or experiments. Because British donation programmes tend to accept and retain full bodies, companies and institutions turn to American human tissue banks, which can provide specific parts, such as torsos or feet.

Once an organisation has used a specimen for training, experimentation or tissue extraction, it needs to dispose of it. Sending the imported specimens back to the United States is expensive, but cremating them in regular crematoria in the UK is illegal. In accordance with their consent forms, American human tissue banks do not disclose the identities of the shipped donors to the British organisations ordering them.

And according to the Cremation Regulations for England and Wales from 2008, bodies whose identities are unknown “should be incinerated or disposed of in some other appropriate way”.

Instead of crematoria, designed for funerals and staffed by technicians trained to facilitate disposal of the dead, the specimens come to industrial waste sites, equipped to efficiently obliterate any thing or substance. What interests me in particular is the special “respectful disposal” procedure these waste contractors are sometimes asked to perform.

As an architect, I study the practices of how these specimens are incinerated. Rather than examining the legal or ethical aspects of this strange industrial process, I looked at its logistical side.

For my field research I visited three high temperature waste incinerators across England and spoke to 18 staff. I studied who performs the procedures, what spaces and containers are used, and how they look and feel. My architectural drawings and sketches offer a close-up look into these details.

At the same time, I asked how do the specimens end up at these sites? Based on interviewing anatomists and regulators, I pieced together the wider narrative of how bodies become disposable.

My research has been published in Social Epistemology and Antipode, presented in a talk in the United States and through a public exhibition in Manchester. I am currently developing a comic book based on my drawings.

‘A body buried is a body wasted’

The body parts, arriving at the waste incinerators in yellow drums, come from the world of human body donation. Given the high funeral costs in the United States, donation offers a free alternative for those who cannot afford a funeral, whether for themselves, a loved one, or someone dying in custody. American human tissue banks take care of the bodies’ disposal, often making a provision for part of the remains to be cremated or incinerated as clinical waste.

Prior to exporting the frozen donated bodies domestically or internationally, the human tissue banks prosect the bodies (divide them into parts); as journalist Jenny Kleeman noted in her recent book, “It’s always more lucrative to sell a dismembered body than a whole cadaver.”

The body parts cross the Atlantic into the UK in coolers or cardboard boxes, arranged by type. For example, an order of ten heads would arrive in a “giant cardboard box”, padded with polystyrene, containing ice packs intermeshed with heads, each one wrapped in absorbing sheet, “with a lemon or cherry smell” – as noted by a donor repository technician.

The body parts come from donors of different racial backgrounds, which surprised another interviewee, who told me: “To unpack a collection of hands from America that were all different skin tones was my first experience of a black body.”

Once in the UK, the body parts are used for a variety of functions. As well as being used to train doctors and medical robots, the human tissues are sometimes used to make new products, such as leg ulcer dressings or pharmaceuticals, as researchers in this field have documented.

A human body is an invaluable source of knowledge and material which can improve the health and opportunities of the living, lending weight to the Victorian saying: “A body buried is a body wasted”.

However useful, certain specimens and their parts become redundant. In the case of surgical training, a head or a torso normally become unusable after two or three times of defrosting and being practised on.

At this point, institutions face a choice. Some (particularly university anatomy departments) opt to repatriate the specimens to the US or the Netherlands through the same tissue banks that delivered them, treating this as a more dignified conclusion to the donation.

Others, for whom repatriation costs are prohibitive, opt for local incineration, which is permitted by the regulator, the Human Tissue Authority (HTA) – provided the disposal is done with respect and “separately from other clinical waste”.

This may seem clear on paper, but how are these stipulations ensured in an industrial facility designed to destroy things as efficiently as possible?

What respect looks like at 1,100°C

When a biomedical school or business decides to dispose of a specimen through incineration, they need to package it as anatomical waste. The appropriate packaging, prescribed by the National Health Service, is typically a rigid plastic container. These are normally yellow cylindrical drums with red lids. A drum may contain several body parts from different people.

Weight, number of containers and waste description, for example “five torsos”, are included in a form to request a special collection (which is different from collecting other “standard” clinical waste). The lab’s staff seal the body parts in the yellow plastic drums that are “one way” in that they are unopenable after sealing.

Once packaged, the waste contractor’s delivery vehicle collects the drums from the researchers and delivers them to the incinerator site. These facilities overwhelm a first-time visitor. The space is cramped, noisy, and smelly. Dozens of tagged containers jostle with workers in coloured hard hats. “Space is a virtue,” one waste manager told me on a walk-along tour, describing his facility as “a testament to how not to do things”.

Hazard warnings and skull-and-crossbones signs cover every surface – unremarkable to the day-to-day staff, unnerving to a visitor.

The delivery of ‘waste’

Warned in advance about the anatomical waste’s delivery, the staff at one of the facilities I visited prioritised it in the loading queue. At most incinerators, there is no cold storage to preserve organic tissues. The site-based chemist incorporates the body parts into the “incineration recipe”: the order of loading waste to ensure the burning happens at a consistent temperature and any violent reactions are neutralised.

Using a lift or a conveyor belt, sealed waste is brought into a space called the chargebox. From there it is rammed into the incineration chamber. The fumes are stringently filtered before being released into the atmosphere. The ashes are sent to a specialist landfill.

The anatomical waste goes through this process, with some exceptions that are made to comply with the HTA’s requests for separation and respect. In some cases, drums are carefully placed into the lift while the other waste streams are paused – though some of the people I met still thought this was disrespectful, since the drums still tumble down into the chargebox.

A more “respectful” solution, practised only occasionally, is where workers bring the waste directly into the chargebox by dismantling an access hatch and exposing themselves to the scorching heat.

On very rare occasions, the disposal procedure is witnessed by a representative of the biomedical organisation sending the waste, or by an invited religious minister. Although I never witnessed this in person, I interviewed an anatomist who routinely followed the drums to the disposal site and heard of two instances of a religious ceremony from workers at an incinerator.

My architectural drawings show these scenes from above and to the side, with no single viewpoint privileged: every drum, every hatch, every worker’s position is given equal weight.

Reading almost like industrial blueprints, the images foreground a key tension in this research: respect is not born from personal sentiment or cultural tradition. It is a set of services, agreed between biomedical researchers and waste managers: improvised last rites that feel counterintuitive in a busy, industrial space.

‘It leaves a bit of a bad feeling’

After learning about respectful disposal at three incinerators, I invited the workers at these sites to group workshops. The aim of the workshops was to get the workers’ opinion on the existing practices and to generate some alternatives. The responses were both pragmatic and effective.

The workshops primarily revealed the workers’ unwillingness to be dealing with anatomical waste.

For example, one male worker in his 40s, said: “Mortuary work is not what we signed up for.”

Anatomical waste makes up less than 1% of what these facilities process. They are normally used to obliterate toxic chemicals and healthcare byproducts. But when it does, the impact lingers. Recounting the incineration of a batch of heads, one worker from Eastern Europe remembered a “bad feeling” when they went home after work.

More senior colleagues managing the process remarked that the rare encounters with the anatomical waste were impacting their colleagues’ mental health. A shift supervisor at one site said: “That just leaves you with everybody going, ‘I don’t feel well now … I need to take a two-hour break at Wetherspoons’.”

But there were some more surprising accounts.

Some younger workers were curious, trying to open and look inside the sealed drums. In response, two experienced colleagues proposed more generic, homogenised forms of packaging, “so that you don’t know what you’re burning”.

That method, they said, would keep “everything enclosed, encased, double bagged … even if lads open it, they can see fuck all.”

Opting to remove acknowledgements of the human remains, the workers came up with intelligent solutions to prevent drums “disrespectfully” toppling over or mixing with other waste. The proposals featured separate doors, cranes to lower the drums gently, and stand-alone mini incinerators operated by a dedicated team.

One incinerator on-duty chemist, in his 40s, remarked that if this was going to be done, then the people carrying it out “are going to bear in mind they are just handling bits of people – it’s not for everyone”.

I also asked workers to draw about their thoughts and what they produced was improvised and to the point. Instead of striving for the right proportions or embellishing the image (as I did), the sketches succinctly focus on what matters: the size of the container, the importance of clear passages, the warning signage to be displayed.

The overarching message from the workshops was clear: the incinerator staff prefer to take a desensitised stance in relation to the anatomical specimens. They want to remain ignorant of the waste, so that they don’t have to worry about it. “What you don’t know won’t hurt you”, remarked a worker in his 50s.

“I don’t think of it as someone’s head or torso … it’s a keg” – said the chemist as we walked away from the rattling shed.

‘Rehumanising the dehumanised’

After the workshops with the waste professionals, I ran interviews and workshops with biomedical and death specialists (which included lawyers, designers, artists and academics). I asked about their role in the industrial disposal of human remains, as well as their suggestions for alternatives.

While broadly aware of the disposal practices, the biomedical respondents were surprised at the ease of human disposal, as well as the injustice towards the imported foreign donors. “This is treating foreign nationals like second class human beings”, said a senior anatomist at a medical school.

A technician from a large donor repository was startled by how easy it seemed to dispose of a dead body if you had access to the right drums. “If you’ve got incineration bins you could quite easily get rid of someone,” he added.

The death specialist group underlined the need for respect. One grief expert responded about dignifying what has already been packaged and classified as waste by saying: “This is re-humanising the de-humanised.”

Some of the death specialists also suggested there needed to be a change in practice and policy.

These specialists wanted the dead to be recognised at the incinerators. But they also felt the real problem started much earlier. Rather than trying to impose respect at an industrial site, they argued, donation consent forms and human tissue policy should be changed so that bodies never end up there in the first place.

The biomedical and death specialists’ views differed from the waste managers’ in the need to acknowledge the presence of human remains. The workers’ sobering proposals for generic, double-bagged containers were met with a different vision of buckets with “calm design”, embellished with iconography like “fragile” and with soft padding.

Whereas the anatomists and death specialists suggested recital of poems, the playing of ceremonial music and creation of soft rooms for mental health support, the waste workers would have none of this. One told me: “I prefer not to think whose leg or torso that is.”

These contrasting positions reveal professional divides along the trajectory of a donated body. What is perceived as a person in a laboratory or a standardised scientific product at a tissue bank, is seen as unpleasant waste in a disposal context.

I drew this full trajectory as a comic, stitching together the divergent viewpoints. What individually appears ad-hoc turns out to be a convenient business plan. The overall picture reveals a system designed so that no one person holds the whole story.

I came away from my experience thinking that the waste personnel’s concealed labour deserves acknowledgement. Similarly to the noble act of donation: their work reshapes our living bodies through the emergence of new doctors, medical techniques and pharmaceuticals. Anatomical waste is part of a complicated process that can help improve society in different ways.

Parts of donated bodies are increasingly unlikely to go through a traditional funeral or cremation. But as biotechnologies advance, more human tissues will end up at industrial incinerators like the ones I visited – their last stop. The yellow drums will keep coming.

As one worker put it: “What you don’t know won’t hurt you.”

But now you know.

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For you: more from our Insights series:

• Kyrgyzstan’s Dordoi Bazaar: a world made from shipping containers and a city within a city

• Britain’s quarter century: wealth and widening inequality

• Free will: does refusing to believe in it make you a ‘bad’ person? Research is challenging this old idea

• Inside Porton Down: what I learned during three years at the UK’s most secretive chemical weapons laboratory

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Mark Shtanov received funding from the University of Manchester as part of SEED Scholarship.