Found: Sci-Fi book about scientists studying primitives on mainland

I got this book over 30 years ago from the Science Fiction Book Club, and the title has escaped me. It opens with two primitive hunters on a hunt. One has a palm print painted on his face. They get too near a restricted area and a large mechanical spider like creature comes out of hiding and catches one of the hunters, but the other hunter, (our protagonist), kills it. Turns out scientists on an island are studying the primatives on the mainland. Eventually the protagonist joins the scientists, as does his nemesis among the tribes. The book follows his life among the tribes, going back to different tribes to study them, and his trying to influence the way the scientists control the natives.

I don't have an answer for you, but when you find it, I want to read this book!!

>1 blsaunders61:

Was the book a Main Selection of the club? Only one of those per month - but they also offered alternate selections, so your number is maybe larger.

ISFDB has more than probably anyone wants to know about the SFBC. Here is 1900-1993, which is approximately 30 years ago.

Looks like The Erthring Cycle by Wayland Drew.

>4 ms529212: That was it. Thanks so much!

>2 AWalkerScott: The Erthring Cycle by Wayland Drew

>3 dukedom_enough: Thanks

>6 blsaunders61: Thanks, looking into it. There are some very cheap copies on Ebay.

>7 blsaunders61: You're welcome