Saturday, February 21, 2009

The Biggest Fish in the World

Yesterday I visited an incredible place - the Georgia Aquarium, biggest aquarium in the world. There were many incredible sights, but the highlight was the whale shark, biggest fish in the world, which outside of Japan and Dubai can only be seen in Georgia. Their largest specimen was only half-grown at 22 feet long, in a six million gallon aquarium. It was truly awesome, and I spontaneously pronounced the berachah of Baruch shekachah lo b'olamo. They also had the world's only captive manta ray, just a baby at 450 pounds - it's expected to reach ten times that weight, with a wingspan of 26 feet!

Friday, February 13, 2009

Washington Heights Lectures

Sunday, February 22nd
Washington Heights Congregation (The Bridge Shul)
815 W. 179th St

7.30 The Challenge of Dinosaurs
8.30 The Dynamics of a Controversy

Admission: $10 (covers both presentations)
Books will be available

Thursday, February 12, 2009

The New York Times on Nishtaneh HaTeva

In the New York Times article to which I linked in the previous post, it says the following:
Researchers have long known that bacteria evolve to evade antibiotics, and that parasites, like those that cause malaria, adapt to drugs used against the disease. More recently, researchers have reported that cod, overfished for decades off New England and the Canadian Maritime Provinces, have begun reproducing at younger ages and smaller sizes. Other scientists have reported similar changes in species as diverse as bighorn sheep, caribou and ginseng plants.

This instantly made me think of the concept of nishtaneh hateva, "nature has changed," an approach that was introduced in the medieval period to account for disparities between the Talmud and the natural world as perceived in that era. This was that the physical nature of the world had changed since the time of the Sages. While this approach has been grossly overextended, its original application is to the case described by the New York Times.
The primary source for this concept stems from a ruling in the Talmud relating to the age at which cattle and donkeys can bear young. Establishing this age is important because a firstborn animal of these species automatically belongs to a Kohen; thus, when purchasing an animal from a non-Jew, one must ascertain if the animal could have given birth already. If not, then when the animal gives birth, the calf must be given to a Kohen. The Talmud rules that if they are three years old, then when they give birth, their first offspring definitely belongs to the Kohen. Tosafos notes that this is contrast to the facts known in his time:
The explanation of this [ruling] is that before they are three years old, they can certainly not have given birth. But this is astonishing – surely we see all the time that two-year-old cows can give birth! One can answer that times have certainly changed from how matters were in earlier generations. (Tosafos to Avodah Zarah 24b s.v. Parah V’chamor)

This is the same as the phenomenon described in the New York Times!

The New York Times on Shiluach HaKein

The New York Times
February 10, 2009
Seeing the Risks of Humanity’s Hand in Species Evolution

According to the sages who issued the Biblical edicts of Deuteronomy, if you come upon a bird’s nest, you may take eggs and nestlings, but you must leave the mother bird behind. “Let the dam go,” the King James version says.

Some consider this advice as odd as many of Deuteronomy’s other injunctions, like its ban on clothing made of blends of linen and wool. It runs counter to the fishing tradition of throwing the small fry back so they can grow up, aiming for the largest males in trophy hunting.

But now some biologists are starting to think Deuteronomy has it right. They see this approach as a remedy for a growing environmental problem — the way human predation is causing target species to evolve to reproduce at younger ages and smaller sizes, to their short-term benefit but to the long-term harm of the species.

(read the rest here)

(Hat tip: Rabbi Steven Miodownik)

Wednesday, February 4, 2009

Lecture Tour Schedule

Here are the details for the public lectures in my forthcoming lecture tour. I still have some gaps in my schedule so please contact me if you want to arrange something.

Wednesday Feb. 11th, 6.30pm:
"How to Avoid Bear Attacks and thereby Save the Jews"
Stern College

Shabbat Feb. 14th:
Young Israel of New Rochelle

Tuesday Feb. 17th, 8.00pm:
"Sacred Monsters"
Ohel David and Shlomo
710 Shore Blvd., Manhattan Beach, Brooklyn

Wednesday Feb. 18th, 7:30pm:
"The Challenge of Dinosaurs"
The Marcus Jewish Community Center of Atlanta
Atlanta, GA
Suggested donation: $18

Shabbat Feb. 21st:
Ahavas Achim, Highland Park NJ