Homo naledi

[busker]

Accidental creatures 
crawling deep into caves
to return their dead 
by flickering firelight
to the original dark.

Brains the size of oranges
they chitter and claw
feasting on antelope.
Predators cannot follow,
cock ears and listen, - the original “they listen at the entrance” had more of a hint of danger. “Cock ears and listen” would be my border collie. Here, detail spoils the charm.

smell smoke and drift on. - the original “drift away in boredom” was okay. Not perfect, but okay. To imply that said predators would drift away only when smelling smoke is, again, a piece of bland detail. Really? Smell smoke? Coming from inside the cave? Enough fire to generate enough smoke to scare away predators? What would that do for the carbon monoxide poisoning situation?


Fresco of time’s children ….. I like the idea of stick figures watching the shadows of those who painted them, but this line is clunky. “Humanity’s lost children” in the original was also true for H Naledi - sized like children, and lost.
watching their shadows
play on the cave walls

their prehensile laughter
does not forget the dead. … so they laugh but don’t forget the dead? I don’t quite follow. Laughter n  our waking the dead, OTOH, was perfect, even though one might wonder why the rhetorical point was being made 
They wait for no God, “expect” in the original sounded better 
no Savior, only sunrise.

Accidental creatures 
crawling deep into caves
to return their dead 
by flickering firelight
to the original dark.

Brains the size of oranges
they chitter and claw
feasting on antelope.
Predators cannot follow
but listen at the entrance

and drift away in boredom
hungry for bigger prey.
Humanity’s lost children
watching their shadows
play on the cave walls

their prehensile laughter
does not wake their dead
they expect no God,
no Savior, only sunrise.

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My overall impression is that you’re tinkering with something that’s fairly close to perfect