Subterranean - James Rollins

Evidence is found of an intelligent civilization beneath the earth in Antarctica. An intelligent civilization that would predate humans by a couple million years. So a group of specialists is gathered to venture into the caverns and explore the geology, biology, and evidence of culture they can find. With a military escort, because what is neglected in the sales pitch is this isn't the first team to be sent down there.

As it goes, this is akin to Natural Selection, which at the time I compared to a more fanciful Michael Crichton book. Really, I think these are more updated Jules Verne stories, just wildly implausible stuff, but it makes for a good adventure. Quick to read, not too complicated, plot keeps moving with limited space devoted to characters struggling with the stresses of their situations. Not no space devoted to it, but not much. Rollins has got places for the story to go. 

The scientists encounter giant predatory creatures that look a bit like a crocodile that walks on hind legs, but have poisonous spines on their backs, because they're actually monotremes (mammals that lay eggs.) There are several varieties of fungus, including one that produces anesthetic spores in response to body heat so it can break down the slumbering prey for food.

And, of course, the subterranean civilization, which are essentially humans, but if they evolved from monotremes rather than placental mammals. And some of them have telepathic abilities, and may have influenced Indigenous Australians. . .somehow. Or interbred with them? The caving expert on the team is apparently Indigenous Australian on his grandmother's side, though he looks like a white dude, and he's somehow able to unlock this same ability.

I mean, these people were in Australia at some point, but the land bridge between it and Antarctica was submerged or otherwise broken, Antarctic surface climate became inhospitable, so they went underground. I'm not sure the timelines line up frankly. I guess maybe if these people were still able to access Australia up to the last Ice Age, but I feel as though they'd have advanced further technologically than they did if they were already able to carve tools and cave dwellings and art underground 5.2 million years ago, as we're told early on.

I know, I know, just go with it for the sake of the story, but this stuff interests me, like the ecology and atmospheric conditions of all those weird-ass planets in the Riddick movies.

There's a romantic subplot about the caving expert and the archaeologist that leads the team feeling attracted to each other, but she's reluctant to open up emotionally. And she's a divorced single mom, so her son is staying at the main base camp and ends up in danger. The biologist is claustrophobic, the geologist is actually a mercenary hired by the diamond companies to make sure the apparent wealth of underground diamonds don't tank their companies, while he also wants to make sure no one finds any oil deposits that could harm the economy of the Middle Eastern nation he hails from. The lead soldier is there because his brother was part of the previous team that went missing.

There's a lot of attempts to add depth to the characters, or give them arcs, but it's all kind of clumsy. Ashley keeps trying to use her archaeological knowledge to help them with this new culture, and she's determined to not make a bad first impression. But every attempt backfires and she keeps having to be protected by the guys. It's caving guy Ben embracing his heritage that makes the breakthrough because he can use his mind powers to bridge the language gap.

'"You feed those monsters? No wonder there are so many of them."

"We must maintain their numbers to produce enough spoor. It is the main goal of the hunters to collect the spoor and bring it back here."

"Shit collectors," Ben said. "So much for the noble hunter image."'