While men are, generally, stronger than women, that is not likely to be your primary concern when talking about societal evolution. Murphy hit the nail on the head with his sentence that stated "many tribal cultures didn't have great population growth and males are thus a little more expendable since losing a few doesn't impact future generations as much". Especially in a treehouse society, mortality rates are going to be high* and that is going to pressure the collective to place a higher value on the people that can give birth to new life.
So question becomes:
with the heightened preference to maintain female lives, why would men stay in the village near the children and elders (the most vulnerable groups, who would generally be in the least vulnerable position possible)?
I think we can come up with a number of requirements and reasons.
1. Hunting is Not Particularly Dangerous
I understand that you stated this world was populated with dinosaurs. Overall that is fine, but I would avoid the trope that the dinosaurs are all basically T-Rex's or raptors as depicted in Jurassic Park. If even a reasonable portion of them are, leaving the village to hunt is going to be exceptionally dangerous. If the females of breeding age were all out in a jungle full of raptors as their primary activity (effectively living the human side of the movie "Predator" every day), the society is going to die off fast. Stick with tiny dinosaurs that might cause injury but probably not death. Large, predatory dinosaurs jungles work better on TV than in reality anyway.
As kingledion suggested in his comment, I would have the hunting parties mainly go after animals like monkeys and fish.
2. Inter-Tribal Warfare is Not Uncommon
Resources are generally hard to come by in a jungle and everyone wants them. Men stay at home to protect the village and scout the area around it.
Note that when a village wants to go to war it does send its men out because they are both stronger and more expendable. This is a very risky move however, as anything less than a sweeping victory may not leave enough males to defend their own village. Additionally, although women are not typically involved in aggressive action they are reasonable defenders, given that they hunt for much of the day.
If you want to play on the dinosaur theme, perhaps the "bad natural enemy" dinosaurs generally stay out of the forest but will come in and attack groups of people. They might not see an advantage in chasing around 1 or 2 hunters who are just going to escape, but when they see a cluster of people they hear dinner bells. Men must fend off or destroy these large beasts until everyone else can get to safety.
3. You Live in Trees - Things Need Lifting and Building
No reason to waste the extra muscle that hangs around the village. Goods and people that cannot climb well themselves frequently need to be moved between treehouse levels and the ground, and men supply the muscle that gets it done. They also perform jobs that involve construction while climbing trees, which is surely quite physically demanding.
I see no reason this couldn't be, logistically is at fault, or is physically impossible. Men absolutely do have certain characteristics that place them at an advantage over women in certain roles (strength, speed, endurance, reaction time) but nothing that would cause a society to decay and crumble if not taken advantage of. What is your metric for 'viable?' – Ranger – 2016-10-19T15:29:12.193
5First, spectacular user name. Second, cultural preference can explain a lot, especially in jungle tribes that historically have a lot of varied gender roles. If you consider that there aren't many large herbivores in the jungle (no grass and few ground level plants to eat) jungle hunting probably means hunting fish or hunting monkeys (or lizards or snakes). There is no physical reason that men would be better suited to shooting poisoned blow-darts at monkeys than women. Sounds viable to me. – kingledion – 2016-10-19T15:34:06.797
2Your race sounds 95% or more like the Klee in DJ McHale's Black Water, part of the Bobby Pendragon series. Jungle dwelling, high tree houses to keep above the dinosaurs, ancestor veneration, elder councils, and early industrial technology- they had it all. Except they were cats, and iirc, were fairly gender-neutral regarding societal roles. – cobaltduck – 2016-10-19T15:34:08.210
1there exist villages in africa where women do the manual labor and the hunt while men stay at home and protect the children or do the politics... – None – 2016-10-19T15:38:24.227
@ Nex Terran, I know "viable" was a vague word choice, but yeah, I mean something along the lines of physical or logistic possibility. – Tyrannohotep – 2016-10-19T16:39:43.257
5You may want to come up with a mechanic such that that hunting is lower mortality than staying in the village, perhaps fixed settlements sometimes get attacked by something large that hunting parties can easily avoid. many tribal cultures didn't have great population growth and males are thus a little more expendable since losing a few doesn't impact future generations as much. – Murphy – 2016-10-19T17:22:27.730
How can they smelt iron in a treehouse? Wouldn't that set the tree on fire??? – cwallenpoole – 2016-10-20T14:46:49.757
5"I'm a sucker for jungle huntress characters" -- so you're writing fantasy for an audience that likes that stuff. Any attempt at an in-universe handwave is going to be jarringly absurd to anybody who gives it a moment's thought, so don't make the attempt. Just present it as a given. Your readers just want to fantasize about hot girls in loincloths killing dinosaurs. So cut to the action. Justifying it is like putting expository dialog in porn. They're just going to skim that part. – Ed Plunkett – 2016-10-20T15:55:33.297
1@EdPlunkett Good point you raise there. :) – Tyrannohotep – 2016-10-20T18:54:57.877
1If not going with Ed Plunkett's proposal, & you want a long term viable society, then you must pay attention to what Murphy & GrinningX stated: The survival of the society's women is far more important for the survival of the society than then the men surviving. To take it to extremes:If you loose 90% of the men, your society can survive, if you loose 90% of the women of child bearing age, your society is dead. Any long term viable society with a limited population will have the women gravitate to roles which have low mortality rates (childbearing already has a fairly high mortality rate). – Makyen – 2016-10-21T16:38:04.040