The meaning of ‘the Indigenous petroglyph was an overwrite’

The meaning of ‘the Indigenous petroglyph was an overwrite’

The passage below is from Fathoms: The World in the Whale Hardcover by Rebecca Giggs.

Stand to one side a moment, to picture it: a seabird dawn, the departing ship faint on the grey horizon. Someone runs their thumb over the newfound text, its little notched serifs, the mystifying, sidewinding S in SHP. CONNECT-I-CUT rolls under their touch and they inquire of the word, its feeling as a sensation; a texture, a sculpture, an animacy. So Connecticut makes landfall soundlessly, dressed in the disguise of its anglicisation, having crossed an earlier border from Algonquian where once it was ‘Quinnehtukqut’ (meaning, ‘beside a long tidal river’). (A touchstone, a dashed track.) What the Yaburara thought, or said, on discovering these foreign incisions, is lost — not because of the attrition of time and memory, but as a result of the genocide and generational traumas that followed. Until microscopic analysis revealed otherwise, researchers suspected that the hatching action might have been the Yaburara striking out the whalers’ words; that the Indigenous petroglyph was an overwrite. But perhaps it was no epiphany to the Yaburara to hear it was the other way around.

The meaning of ‘the Indigenous petroglyph was an overwrite’.

Here does ‘the Indigenous petroglyph’ refer to the Yaburara hatching?

(I’m asking this because I’m wondering if hatching could be called petroglyph.)

Am I right? (Then you don’t need to read the following.)

If I’m wrong another question comes up.

Overwrite means to destroy (old data) by recording new data over it.

But why does ‘the Indigenous petroglyph’ became ‘an overwrite’, I have no idea.

Thanks in advance.