The furore over a film portraying the 19th-century palaeontologist Mary Anning as having a female lover probably tells us more about ourselves than it does about historical accuracy onscreen. Francis Lee’s Ammonite might not be a scrupulously backed-up biopic, but it may just hit on the one thing that so many other accounts of Anning, and other early women in science, have missed: the importance of friendships and collaborations.

Anning, the working-class woman whose fossil discoveries changed the world, and a modern-day icon for women in science, is once again making news. This time, however, it’s not the ancient creatures she unearthed causing the stir. Kate Winslet will play her in the new movie, and her fellow actor Saoirse Ronan has confirmed that her character, widely reported in the press as Frances Bell (a real person and friend of Anning) and Mary Anning are lovers. Cue media frenzy, with plenty of opportunity for outrage over (presumed) historical inaccuracy and claims of sexing-up an already remarkable biography, alongside salacious delight at the thought of a lesbian love affair amid the Lias.

Let’s get one thing straight: there is absolutely no evidence that Anning and Bell were lovers. But getting your knickers in a twist over a lesbian storyline, and crying “historical inaccuracy” on this count only holds water if you assume heterosexuality and/or celibacy for Anning until proven otherwise.

So what do we know? The real Frances Bell was just 14 when she visited Lyme Regis in 1824. She became friends with Anning, 10 years her senior, who taught her about fossils, and helped her create a small personal collection including an ammonite that glittered gold with iron pyrite.

Although brief – Bell died the following year – their friendship seems to have been intense and shot through with vulnerabilty. Letters show that Anning became upset when Bell did not write to her immediately after leaving Lyme Regis. Bell described Anning as one of her two friends, but that time would show “which of these two will prove the most faithful”, a sentence that makes the heart ache for her. But otherwise their short correspondence is characterised by religious observations, and delight over fossils and the British Museum. Sexy it is not.

In contrast, Saoirse Ronan’s character in Ammonite is described as a gentlewoman “encouraged by her husband to get a hobby”, who stays with Anning and learns about fossils. Rather than the 14-year-old Bell, this sounds more like a naive Charlotte Murchison, who came to learn fossiling with Anning at what proved to be the start of a long friendship.

It seems, then, that the Bell in Ammonite is actually an amalgamation of different women who touched Anning’s life – and there are many to choose from. Anning, charismatic and clever, clearly inspired affection. Another young friend, Anna Maria Pinney, wrote: “I really love Mary Anning.” And there were the Philpot sisters, who mentored and nurtured young Anning’s interest in geology, and Mary Buckland.

These women were all active in geological research, corresponding with each other, sharing notes and fossils and ideas. Murchison’s and Buckland’s legacies are mostly obscured by their husbands’ (Roderick and William, respectively) greater fame, but they were linchpins in this network of women connecting Anning with the fashionable academic salons of the day. As previously noted by TrowelBlazers’ Suzanne Pilaar Birch, Anning wasn’t the only 19th-century woman collecting fossils on the seashore.

Anning was a genuine legend in her own time. But, as is true of many working-class historical figures, precious few documents exist to tell us about the detail of her personal life. We instead have to piece together a picture from scattered snippets in the recollections of others. Was she a “prim, pedantic vinegar woman” (Gideon Mantell), or “the proudest, most unyielding spirit … [who] glories in being afraid of no one, and in saying anything she pleases” (her friend Anna Maria Pinney)? This leaves plenty of room for everyone to create their own personal Mary Anning.

Lee’s Ammonite will be another contribution to the rich and varied mythology that has grown up around Lyme Regis’s most famous resident. And, rather than perpetrating a historical inaccuracy, it could be that by putting the women in Anning’s life at the centre of his fictional reimagining, Lee may end up telling a genuinely overlooked truth about the history of geology: the vital contribution of, and collaboration between, women.

• Tori Herridge and Becky Wragg Sykes are co-founders of TrowelBlazers, which tells the forgotten stories of women in geology, palaeontology and archaeology

• This article was amended on 20 March 2019 in the light of the following addendum from the writers:

After publication of this article, spokespeople for Ammonite got in touch with us to confirm that we were correct in guessing that Saoirse Ronan would be playing Charlotte Murchison and not Frances Bell, as has been widely reported. What do we know about Anning and Murchison? After meeting in Lyme Regis in 1825, it was with Murchison that Anning stayed on her one and only trip to London in 1829. Their friendship and correspondence is apparent in 1833, when Anning writes to tell the news of her dog Tray’s death in a landslide.

In casting Ronan, the relative ages of Anning and Murchison have been upended, perhaps allowing for elements of Anning’s other female relationships, including that with Bell, to be drawn upon. And the real Murchison was far more than a wealthy lady whose’s husband thought she should get a hobby. This was the woman of whom the artist Henry De la Beche – also a friend and supporter of Anning’s – wrote “shines the light of science, dispelling the darkness which covers the world”. She also protested against Charles Lyell’s refusal to allow women to attend his geological lecture, and is credited with building her husband’s illustrious career, turning him from a foxhunting dilettante into a serious man of science and eventual director general of the British Geological Survey. Let’s hope Ammonite captures the brilliance and strength of both Murchison and Anning, as well as the many other women, who helped shaped the field of geology from its beginnings