This Parsha teaches us about the species that are permitted or forbidden for consumption. As usually, we are not going to ask for a lengthy commentary but rather we would like to know some general rules and reasons why particular animals are forbidden?
In this Parsha, the Torah describes to us the forbidden mammals, birds, fish and other species. It’s impossible to dwell on all of these in our short commentary but we will concentrate only on the mammals. Obviously we can discuss the dietary laws on various levels of interpretation. We could mention the health benefits, the zoological analysis, the spiritual reasons, or how these laws hint to other ideas. Since it’s impossible to cover all these topics we will primarily stop at the last two. We will discuss the general nature of the forbidden species as well as some of the hints related to the topic.
Regarding the mammals, the Torah gives us two signs to distinguish the kosher ones from the ones that are forbidden. The mammal has to have hooves that are split and it has to chew its’ cud. The explanation of these two signs is as follows. A hoof is a kind of hard surface covering the bottom of the foot. Most of the mammals don’t have any hoof at all. Some have a hoof but it is not split. The Torah requires that a mammal have a hoof and that it is split. Chewing the cud means chewing the food more than once. Such animals are generally called “ruminating”. After eating some grass they pass it to one of their stomachs and let it stay there for a while. Then they bring it up again in a form of a lump, chew it a second time and then swallow it again.
In Parshas Ree (Devarim 14:5), the Torah mentions ten species of kosher mammals. Four of the non-kosher mammals are mentioned explicitly in this Parsha because they have one kosher signs each. Three of these animals (camel, rabbit and hyrax) have the “external” sign of kashrus. They chew their cud but don’t have a fully split hoof. One animal – the pig has a split hoof and does not chew its’ cud. The GR”A explains that two signs of kashrus hint to the control over two main bad qualities: anger and desire. The opposite of these two qualities is calmness and satisfaction.
The ruminating animals are an
example of being satisfied with one’s lot. Always busy chewing what they
already swallowed they are thus happy with what they have.
Our sages teach that there is a
great significance in regards to these four animals. They correspond to the
four nations that ruled over the civilized world throughout the history:
 Another kosher sign of animals according to some opinions is the possession of horns (see Mishna, Nidah 6:9, see however Tosafos, Chulin 59a starting with words “Eilu Hen”; see Magen Avraham on Orach Chaim 586:3). See also Ramchal, Adir Bamarom (pg. 385), in the discussion about the fourth kingdom for the spiritual reason behind this sign.
 See the likutim of the GR”A on Agados Bava Kama printed in Gnuzos HAGR”A, pg. 289 that the general order of the ten kosher species corresponds to the ten Sefiros. The three domestic animals correspond to the three higher Sefiros, and the seven wild kosher animals correspond to the seven lower Sefiros in the same order. “Zemer” (giraffe) thus being the most beautiful animal corresponds to Malchus, (the word “Zemer” also means a song).
 All other non-kosher animals have neither sign. This statement has been checked by zoologists and is thus offered as an interesting proof for validity of the Torah (see Talmud, Chulin 60b; Maharatz Chiyus 59a).
 Regarding why rabbit and hyrax are considered to “chew their cud” see “Sichas Chulin” pg. 410 and “The Living Torah”, pg. 545. At any rate these two animals are not considered in the category of regular ruminating animals. This is hinted to in the Talmud (Chulin 59a) and Rambam, (Laws of forbidden foods 1:2): “There are no other ruminating non-kosher animals except the camel.” The Rishonim ask: “What about the other two mentioned in the Torah?” According to this, the answer is that the other two are not exactly “ruminating” though they do eat the same food twice like the ruminating animals (Sichas Chulin).
 These two qualities also correspond to the two main gentile nations: Eisav and Yishmoel and to the commandments: not to kill and not to commit adultery, (see also our words to Parshas Noach).
 See also Kol Bo in the beginning of the laws of treifos, that ruminating animals are often pursued by the predators, so they may not have enough time to eat. This is why they swallow a lot of grass right away and then chew it one more time when they get a chance.
also the GR”A’s commentary to Agados, Bechoros 8b, starting with words: “Aiti
Budia”. He writes that the word “
 It is certainly true that the animals that have no hoof at all but have paws, are usually predators, while the ones with the hoofs eat grass. The GR”A does not explain why the “split” hoof is an additional sign of calmness. It may be that when the hoof exists, but is not split, the animal has better chance of kicking or running and is predisposed to war, (see Talmud, Pesachim 113b regarding the horse; Yoma 49a regarding the mules).
 Idolatry, murder, and forbidden relations. Obviously this does not mean the entire nation had these sins, but as usual we are judged collectively, especially when the righteous could try to stop the wicked and did not do so, (see also Talmud, Shabbos 55a).
 In the words of the Talmud (Yoma 9b) “The early ones had their sins revealed and the end of their exile revealed, the later ones did not have their sins revealed nor the end of their exile”. See our words to Parshas Bechukosai.
 We were redeemed from the first three nations in the merit of Avraham, Yitzchak and Yakov, while the last exile corresponds to Moshe. The redemption of the three types of “firstborn” (firstborn of a man, of a kosher animal and of non-kosher animal) corresponds to the first three dominions. The last exile corresponds to Maaser of animals that does not get redeemed. We will be come out of this exile only through our own repentance and through studying the Torah of Moshe, (see the GR”A to the Zohar in Yahel Ohr, 2:115a; 3:178b).