Monster intelligence, part 1: beasts

As an exercise, I decided to look up and compare the intelligence scores of the monsters in the MM. I was aided in this by a brief analysis of what intelligence scores supposedly measure and a spreadsheet listing the ability scores of all the monsters in the MM (see the links below). Thus, I decided to make a series outlining my findings. For my first post, I decided to look at beasts.

In 5e, beasts are not restricted in intelligence or alignment compared to animals in 3e. Generally, those in the MM have intelligence scores less than or equal to three (≤3) and are unaligned. 5e does not specify whether there is a minimum intelligence score required to understand and speak languages, but generally only beasts of "low intelligence" or higher (6+) will be able to understand but not necessarily speak one or more languages. I can only imagine how difficult it is to learn a language while physically unable to speak it.

Relative intelligence of beasts

• “Non-intelligent” (1): Constrictor Snake, Crab, Frog, Giant Centipede, Giant Constrictor Snake, Giant Crab, Giant Fire Beetle, Giant Scorpion, Giant Shark, Giant Wasp, Hunter Shark, Lizard, Poisonous Snake, Quipper, Reef Shark, Scorpion, Sea Horse, Spider, Swarm of Insects, Swarm of Poisonous Snakes, Swarm of Quippers
• Commentary: generally amphibians, fish, reptiles and invertebrates.
• “Animal intelligence” (2-3): Allosaurus, Ankylosaurus, Axe Beak, Badger, Bat, Black Bear, Blood Hawk, Boar, Brown Bear, Camel, Cat, Crocodile, Deer, Dire Wolf, Draft Horse, Eagle, Elephant, Elk, Flying Snake, Giant Badger, Giant Bat, Giant Boar, Giant Crocodile, Giant Frog, Giant Goat, Giant Hyena, Giant Lizard, Giant Poisonous Snake, Giant Rat, Giant Sea Horse, Giant Spider, Giant Toad, Giant Wolf Spider, Goat, Hawk, Hyena, Jackal, Killer Whale, Lion, Mammoth, Mastiff, Mule, Octopus, Owl, Panther, Plesiosaurus, Polar Bear, Pony, Pteranodon, Rat, Raven, Rhinoceros, Riding Horse, Saber-Toothed Tiger, Stirge, Swarm of Bats, Swarm of Rats, Swarm of Ravens, Tiger, Triceratops, Tyrannosaurus Rex, Vulture, Warhorse, Weasel, Wolf
• Commentary: generally birds, dinosaurs and mammals.
• “semi-intelligent” (4-5): Baboon, Giant Octopus, Giant Weasel
• Commentary: primates seem to be rated fairly accurately in comparison to reality, but the others are clearly arbitrary. Not that I was expecting the MM to be accurate to real studies of animal intelligence.
• “low intelligence” (6-7): Ape, Giant Ape, Giant Elk, Giant Vulture
• Commentary: the apes have no languages, even though they can learn sign language in reality. Giant elks speak their own language and can understand two others. Giant vultures can understand Common but cannot speak at all, raising the question of how they learn it; they are the only beasts in the MM with an alignment (NE).
• “dull-witted” (8-9): Giant Eagle, Giant Owl
• Commentary: like the giant elk, the giant eagles and owls speak their own language and understand a couple others. I am pretty sure this is solely due to Tolkien's use of them in The Hobbit and The Lord of the Rings.

Relevant links

• http://luduscarcerum.blogspot.com/2015/09/non-human-animals-in-d-35e.html
• http://www.enworld.org/forum/showthread.php?562175-Intelligence-Ratings
• https://www.reddit.com/r/DnD/comments/6o8m8v/5e_monster_spreadsheet_with_ability_scores_which/