Pt3 Patterns in Animal and Plant Reproduction According to the Talmud, with Comparison With Modern Biological Scientific Knowledge (Bekhorot 7b-8a)

The gestation periods of various animals and their parallels in the plant kingdom - List of 11 animals and their corresponding plants

This is the third and final part of a 3-part series. First part here; second part here.

Pt5 - The gestation periods of various animals and their parallels in the plant kingdom - List of 11 animals and their corresponding plants

Bekhorot 8a (sections # 12-14)

This Talmudic passage explores the gestation periods of various animals and their parallels in the plant kingdom. It starts by comparing the gestation or hatching times of animals to the maturation periods of certain trees and plants. 

For example, it’s stated that a chicken hatches in 21 days, similar to how an almond ripens in the same duration. Other comparisons include dogs and figs, cats and mulberries, pigs and apples, with more extended periods noted for larger or more exotic animals and corresponding plants.

Comparison With Modern Biological Scientific Knowledge

Most of the gestation periods for animals and corresponding ripening times for plants in the claim are problematic when compared to known biological and botanical cycles.¹

Interestingly, the Talmud is exactly correct only for the gestation periods of chickens, sheep, goats, and cows. Which makes sense, since those animals are kosher, so the Talmudic sages would be most familiar with them.

Similarly, they’re most accurate with wheat (“grain” - תבואה) and grapevines, stating that it takes 5-6 months to “gestate”, presumably referring to the annual cycle of fruit ripening; i.e., from the development of flower buds to the ripening of fruit. Wheat and grapes would likely be fruits that the Talmudic sages would be especially familiar with, since they were highly important food crops in the classical Middle East and Mediterranean.

(After this section, there’s a table that summarizes the following discussion.)

1. Gestation Periods:

   1. Chickens (תרנגולת) - It is accurate that a chicken's eggs typically hatch after about 21 days of incubation.²

   2. Dogs (כלב) - The gestation period for dogs is generally around 58-68 days, commonly rounded to about 63 days.³ The claim of 50 days is around 8% shorter than the actual average gestation period.

   3. Cats (חתול) - Cats have a gestation period of about 64-67 days, not 52 days as claimed.⁴ So again around 8% shorter than the actual average gestation period.

   4. Pigs (חזיר) - Pigs have a gestation period of approximately 114 days, known colloquially as "three months, three weeks, and three days," which is significantly longer than the 60 days mentioned.⁵

   5. Foxes and Creeping Animals (שועל וכל מיני שרצים) - Foxes have a gestation period of around 51-53 days, which is much less than six months.⁶ "Creeping [animals]" is a broad category, but many such animals do not have gestation periods anywhere near six months.⁷

   6. Sheep and Goats (בהמה דקה טהורה): Correct, typically around 5 months.

   7. Camels and Donkeys (בהמה גסה טמאה): Correct for camels (about 13 months) but slightly exaggerated for donkeys (about 12 months, whereas actual is closer to 14 months).

   8. Cows (טהורה): Correct, about 9 months.

   9. Wolves, Lions, Bears, Leopards, and Others (הזאב, והארי, והדוב, והנמר, והברדלס, והפיל, והקוף, והקיפוף): Incorrect. Gestation periods for these animals are much shorter (e.g., lions about 110 days, elephants about 22 months. See the table in the next section for specific times).

   10. Vipers (אפעה): Highly incorrect. Vipers have a gestation period of a few months, not 70 years.

   11. Snakes (נחש): A 70 year gestation is highly exaggerated. Most snakes have gestation periods of a few weeks to a few months, depending on the species. But it’s likely that “70” is a typological number, and simply means “a long time”. (However, the ensuing Talmudic story implies that this number was taken somewhat literally.) But it’s still unclear as to why snakes would be seen to have a relatively long gestation period.

2. Tree and plant Maturation:⁸

   1. Almonds (לוז) - The claim that almonds ripen 21 days after the budding of the flower is inaccurate. Almond trees flower early in the spring and the fruits take several months to mature. The ripening typically occurs in late summer or early fall, not just 21 days after flowering.⁹

   2. Figs (תאינה) - Figs do not have a specific gestation period that aligns with the claim of 50 days for dogs. Figs typically have two crops per year, and the time from flowering to ripe fruit depends on the variety and local conditions, but it is generally longer than 50 days.

   3. Mulberries (תות) - Mulberries take longer to ripen than 52 days from flowering. The fruit usually matures over several months, similar to many other fruit trees.

   4. Apples (תפוח) - Apple trees bloom in spring and the fruits mature in late summer to autumn, taking several months from flowering to fruit maturity, not just 60 days.

   5. Grain (תבואה) - The growth cycle for grains like wheat or barley from planting to harvest typically ranges from 3 to 6 months depending on the variety and environmental conditions.

   6. Grapevines (גפן) - Grapes reach maturity for harvest annually within a single growing season (a few months) each year after the vine has matured.

   7. Date Palms (דקל) - The claim that the maturation period of a date palm corresponds to the 12-month gestation period of camels or donkeys is inaccurate. Date palms can take 4-7 years to start producing fruit after being planted, and they reach full production capacity around 10 years, far exceeding a 12-month cycle.

   8. Olives (זית) - Olives do not have a growth cycle that corresponds directly with the nine-month gestation period of cows. Olive trees typically begin to bear fruit within 3-5 years after planting, and their fruit also matures annually.

   9. White Fig (בנות שוח) - Fig trees can start producing fruit within a few years after planting. Maybe this is what is meant by a three-year maturation cycle that would correspond to a gestation period of three years.

   10. Carob Trees (חרוב): It's highly exaggerated that carobs take 70 years to mature; they start bearing fruit typically within 6 to 20 years after planting. But it’s likely that “70” is a typological number, and simply means “a long time”, in which case this can be considered accurate.¹⁰

   11. Mukhsasim (מוכססים): Jastrow: “a species of figs”. In general, fig trees, including various species, start bearing fruit within a few years after planting. Typically, fig trees begin to produce a small number of fruits as early as the second or third year, and they reach full productivity around five to seven years. The ripening of figs happens annually once the tree is mature enough to bear fruit. The specific claim that mukhsasim figs take seven years to ripen is likely emphasizing the time it takes for the tree to reach full maturity and consistent fruit production rather than the annual cycle of fruit ripening. Therefore, it is broadly in the range of typical maturation times for fig trees to fully establish and produce a consistent and abundant yield.

Table, based on the passage

ת"ר: 

1. תרנגולת: לעשרים ואחד יום, וכנגדה באילן: לוז 

2. כלב: לחמשים יום, וכנגדו באילן: תאינה 

3. חתול: לחמשים ושנים יום, וכנגדו באילן: תות 

4. חזיר: לששים יום, כנגדו באילן: תפוח 

5. שועל וכל מיני שרצים: ששה חדשים, וכנגדם באילן: תבואה

6. בהמה דקה טהורה: לחמשה חדשים, וכנגדן באילן: גפן 

7. בהמה גסה טמאה: לשנים עשר חודש, וכנגדו באילן: דקל 

8. טהורה: לתשעה חדשים, וכנגדה באילן: זית 

9. הזאב, והארי, והדוב, והנמר, והברדלס, והפיל, והקוף, והקיפוף: לשלש שנים, וכנגדן באילן: בנות שוח

10. אפעה: לשבעים שנה, וכנגדו באילן: חרוב. חרוב זה: משעת נטיעתו עד שעת גמר פירותיו שבעים שנה. וימי עיבורו שלש שנים 

11. נחש: לשבע שנים, ולאותו רשע לא מצינו חבר, ויש אומרים: מוכססים

The Gemara cites a baraita that discusses the length of gestation for various animals. The Sages taught that: 

1. A chicken hatches after 21 days, and corresponding to it in length of gestation with regard to trees is the almond, which ripens 21 days after the budding of the flower. 

2. A dog gives birth after 50 days, and corresponding to it with regard to trees is the fig. 

3. A cat gives birth after 52 days, and corresponding to it with regard to trees is the mulberry. 

4. A pig gives birth after 60 days, and corresponding to it with regard to trees is the apple. 

5. A fox and all types of creeping animals give birth after 6 months, and corresponding to them with regard to trees, i.e., plants, is grain.

6. Small kosher livestock, such as sheep or goats, give birth after 5 months, and corresponding to them with regard to trees is the grapevine. 

7. Large non-kosher livestock, such as camels or donkeys, give birth after 12 months, and corresponding to them with regard to trees is the date palm. 

8. Large kosher livestock, such as cows, give birth after 9 months, and corresponding to them with regard to trees is the olive. 

9. The wolf, and the lion, and the bear, and the leopard, and the bardelas, and the elephant, and the monkey, and the long-tailed ape give birth after 3 years, and corresponding to them with regard to trees is the white fig.

10. A viper gives birth after 70 years, and corresponding to it with regard to trees is the carob. In the case of this carob, the period from the time of its planting until the time of the ripening of its fruit is 70 years, and the length of its gestation is three years. 

11. A snake is born after 7 years, and for that wicked animal we have not found a counterpart among trees. And some say that mukhsasim are the equivalent, as they ripen after seven years.

1. For a relevant list, see List of mammalian gestation durations - Wikipedia.

2. Incubator (egg) - Wikipedia > “Purposes”:

“Chicken eggs are recorded to hatch after about 21 days [...]”.

3. Dog - Wikipedia > “Reproduction”:

“Dogs bear their litters roughly 58 to 68 days after fertilization, with an average of 63 days, although the length of gestation can vary. ”

4. Kitten - Wikipedia > “Development”:

“Kittens are typically born after a gestation lasting between 64 and 67 days, with an average length of 66 days. ”

5. Pig - Wikipedia > “Reproduction”:

“The gestation period averages 112–120 days.”

Maybe the Talmud (meaning, the beraita quoted) was much less aware of Pigs’ gestation, since they aren’t kosher, and aren’t kept as pets?

6. Fox - Wikipedia > “Sexual characteristics”:

“Once the egg is fertilized, the vixen enters a period of gestation that can last from 52 to 53 days.”

7. The terms “creeping [animals]” (שרצים - sh’ratzim) refer in the Bible and Talmudic literature to small animals like lizards, snails, and frogs.

See these Wikipedia entries:

1. שרצים (יהדות) – ויקיפדיה

2. שמונה שרצים – ויקיפדיה

3. Eight sheratzim

The first entry, in Hebrew, defines sheratzim as follows (my translation):

Sheratzim are a group of animals defined separately in Judaism from other animals, with regard to several halachic laws.

Sheratzim are all the animals whose bodies are close to the ground (short legs or no legs), and are not halachically defined as birds, fish, wild animals, or livestock (כעופות, דגים, חיות או בהמות). This group includes animals from many categories, and has no equivalent in the scientific classification of animals. The group includes: mammals (such as mice), reptiles (lizards), amphibians (frogs), insects, and more.

Halacha discusses sheratzim in terms of laws of Shabbat, laws of tumah from sheratzim, laws prohibiting the consumption of blood, laws of ever min ha-chai (אבר מן החי), and more.

To return to the subject of our Talmudic sugya, the gestation or development periods for creatures typically referred to as "שרצים" (sheratzim) can vary widely, because, as mentioned, this group includes a broad range of invertebrates and some small vertebrates. But they typically range from a few days to a few weeks, far less than the 6 months stated by the Talmud.

8. Throughout, with these numbers, it’s unclear if “gestation” is referring to:

A) the time it takes for the tree to reach full maturity and consistent fruit production -  this period is typically several years; or

B) the annual cycle of fruit ripening, meaning, from the development of flower buds to the ripening of fruit.

It’s possible that it changes, based on context, and this is how I assume.

9. Almond - Wikipedia > “Description”:

“The fruit matures in the autumn, 7–8 months after flowering.”

10. Several other trees also take a long time to start producing fruit. A few examples:

1. Avocado - 5 to 13 years

2. Pecan - 10 to 15 years

3. Walnut - 10 to 13 years