Do animal companions get bonus attacks due to high BAB?

Question

I'm looking for an entry in the rules that tells me that animal companions do not get additional attacks with a high BAB bonus. But I can't find anything.

The only thing I found was this example in the "rules of the game" column on the wizards page:

For example, a wolf animal companion with a 9th-level master has 8 Hit Dice (2 racial Hit Dice and 6 bonus Hit Dice), a base attack bonus of +6, and a Strength score of 16 (base 13 increased by 3). The wolf companion attack bonus with its bite is +9 (+6 base, +3 Strength). Because a wolf has only one natural weapon (its bite), the wolf gains a second bite attack when it uses the full attack action. The attack bonus for this second attack is +4 (9 - 5).

so, is that correct and why? who gets a second attack at BAB +6 and who doesn't? and where is it in the rules?

EDIT:

what I also found is this clear statement ... but this is from the pathfinder rules so I am not sure if the same is true for 3.5:

Animal companions do not gain additional attacks using their natural weapons for a high base attack bonus.

Answer 1

No. From the SRD, Natural Weapons:

Creatures do not receive additional attacks from a high base attack bonus when using natural weapons.

The "Rules of the Game" column is describing the effects of a Druid class feature, which grants Multiattack to animal companions even if they don't have the prerequisites, and grants a bonus attack if they normally have only one attack. The extra attack has nothing to do with BAB and two attacks is all that Druid's wolf can have, regardless of the Druid's level.

Answer 2

No, they do not. An animal companion's weapon is a natural weapon.

All natural weapons lack iterative attacks

But to be clear, this is a property of natural weapons, not Animal Companions.

Animal Companions could get iteratives, if they have a manufactured weapon

If an Animal Companion, as absurd as it may initially seem, wields a manufactured weapon, it would get iteratives. For example, the Mouthpick from Lords of Madness is a magic weapon that can be wielded proficiently by any creature that has a Bite attack: with one of these, your Wolf would get iteratives based on its BAB (and look very silly).

More reasonably, some Animal Companions are primates that might wield a club or similar.

The Other Exception

Improved Rapidstrike from Draconomicon gives a pair of natural weapons (a pair of Claws, a pair of Wing Buffets, whatever) iteratives. Animals don’t qualify, but Elementals, Magical Beasts, and Plants do, if any of those show up on any Animal Companion lists. (Aberrations and Dragons are the other qualifying types, but I really doubt any of those are available as an Animal Companion)