I am wondering why snakes no longer talk. The Lord punished the serpent by making him crawl on his belly and eat dust, and be at odds with Eve's offspring, but it does not mention taking away the serpents power of speech.
It's pretty hard to ask any questions from the first two chapters of Genesis, considering both the esoteric nature of both the topic and the fact that the world seems to have rather different back then in a way that may be inherently incomprehensible for us now that we've been evicted from Eden.
That being said, there are several approaches to this question. (The first three here are quoted by the Ibn Ezra)
It could be that the snake in the story is not literally a snake, but a metaphor for the Satan, or some similar evil force. The Ibn
Ezra himself rejects this opinion, though there are several
midrashim that seem to take this view, despite the obvious problem
of God punishing the 'snake' by making it crawl on the ground.
Chava was a wise enough person to understand snake language (a
R. Saadia Gaon says that an angel spoke for the snake, even though
the 'evil plan' or whatever it was that he did wrong was his own
fault (the angel just helped give him a voice)
Ibn Ezra himself does believe that pre-tree snakes could talk, and
though he doesn't mention this lack of punishment, he might reply
that by losing his ability to eat normal food and walk on 'legs' are
symbolic of becoming less human-like and indicate a loss of the
ability to speak as well.
Abarbanel writes that the snake never actually spoke, and though the
Torah states that he spoke, it means that he gestured in way that
his message to Chava was obvious (such as by continually eating from
the tree, and shoving Chava into it, etc.)
The Lubavitcher Rebbe discusses this at length according to Rashi and the plain meaning of the verses (there are others who say that the very ability to speak was something just special for that occasion). He brings up a two possibilities:
It is obvious. Everyone sees snakes don't talk, so there is no need to specify that this was included. (He rejects this explanation).
The taking away of the ability to speak is included in the fact that it was cursed more than all other animals. If it retained the ability to speak, it would not be worse than all the other animals.
The second is referenced by the verse saying "Because you did this you will be cursed ..." That which gave it the ability to do entice Chava into the sin is what was removed from it. Both the ability to speak, and its cunning over the other animals (thus it became lower than the other animals).
The Moshav Zekanim al haTorah (3:4) brings that prior to dor haflaga everyone spoke the same language, as the pasuk states: vayihi khol haarets safa echat udvarim achadim (bereishis 11:1), including the animals.
After the dispersion took place, everything went south.