I said in mine heart concerning the estate of the sons of men, that God might manifest them, and that they might see that they themselves are beasts. Eccl 3:18
This passage is an excellent example of what is taught in 1 Cor 2:14:
But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned.
The reference to the sons of men refers unto those who are born of male and female seeing that man is male/female. Even Jesus teaches in
Matthew 19:4 that it was not man and woman, yet being the Son of man the mystery of the Woman should be understood from his statement in Matthew 23:9 about calling no man on earth your father.
However, there is no question that the LORD is the God of all flesh, as written in Jeremiah 32:27, "Behold, I am the LORD, the God of all flesh:..." and God is the God of all spirits of all flesh, but the LORD is the Father of all living souls. While it is written in Genesis 2:7,
"And the LORD God formed man of the dust of the ground, and breathed into his nostrils the breath of life; ..." Yet the dust of the ground refers to the body of light in Genesis 1:1 that created the heaven and the earth.
And while it is not an incorrect interpretation that the breath is pnuema, (forced air, or breath/wind), it is an error to interpret the soul as being pneuma. This can be discerned the from Genesis 7:22,
"All in whose nostrils was the breath of life, of all that was in the dry land, died."
However, one can consider these two passages in 1 Kings 17;
17 And it came to pass after these things, that the son of the woman, the mistress of the house, fell sick; and his sickness was so sore, that there was no breath left in him.
and
24 And the woman said to Elijah, Now by this I know that thou art a man of God, and that the word of the LORD in thy mouth is truth.
So to answer the question on whether there are animals in heaven, it is possible but the scriptures definitively reveal that the serpents won't be.
19
For that which befalleth the sons of men befalleth beasts; even one thing befalleth them: as the one dieth, so dieth the other; yea, they have all one breath; so that a man hath no preeminence above a beast: for all is vanity. 20
All go unto one place; all are of the dust, and all turn to dust again. Eccl 3:19-20