Okay, firstly, this game is extremely similar to Era of Terror. A potential reason that there are so many dislikes is because it does not deviate from the standards it has set. Ancient Earth is not its own, distinct game; it has much more profitable and indomitable competition.
As a developer, you are selling your game as original content. Although I do not doubt for one moment that your game has content that you or your co-developer(s) have not made personally, it lacks the pizzazz required to exalt itself as an independent, respected game.
Despite that, these are the visible issues that I have found.
Building
Despite having good scripting, the building in your game is lacking. Terrain is unrealistic, the map is small, and shrubbery is highly inconsistent to the appearance of trees.
This 'bridge' is steep and unrealistic.
There is no riverbed.
The caves themselves are made simply and easily, eroded away with the delete tool. The map itself is small and surrounded by unrealistic mountains. I can’t visibly see any areas in which there has been an effort made to make the terrain extremely realistic. People play dinosaur games because they expect realism.
Gameplay
Concerning gameplay, there is simply nothing to do. Attack other dinosaurs? Okay. Eat? Alright. What else? There are no complex fighting mechanics with blood and decay. There are no carcasses of dinosaurs left in the wild. In terms of lighting, there are no sun rays, no complex terrain or a range of selection and this really inhibits progression. As well as for the factor of domination, people play these games to roleplay, but I found that I was only locked to a small range of dinosaurs to play as. This will turn players away quicker than anything.
The map was small and without much to do, I was bored within thirty seconds. Especially when I saw that the chat was filled with people who weren’t really doing much. Within a more realistic game, you might find roleplayers who are interested in the game and its mechanics, but your game clearly hasn’t reached that demographic.
I’d say the UI is also too big. It fills up the screen a lot. A smaller UI at the bottom of the screen would be much more visibly attractive.
"Example of nicer bar UI (Roman Parthia by MarkAntonius)

Conclusion
Add more realistic features in terrain and make your gameplay more inclusive. Add more to do, potentially rework the models to be more realistic. I’m not sure anybody above the age of eight is particularly interested in cartoony, blocky dinosaurs. But that might just be me.
Give your game a USP that sets it apart from Era of Terror.