By Ran Shapira, Haaretz Correspondent   
Tags: Joseph, Archaeology  
The remains of a burnt beetle found in a grain of wheat about 3,500 years old provided a group of researchers from Bar-Ilan University with a key to a question the Bible left without a definite answer: How did Joseph the Dreamer, who became the viceroy to the king of Egypt, succeed in preserving the grain during the seven lean years and prevent Egypt's population from starving?
According to the description in the book of Genesis, during the seven years of plenty in Egypt, Joseph had all the wheat collected in silos. "And he gathered up all the food of the seven years which were in the land of Egypt, and laid up the food in the cities; the food of
the field, which was round about every city, laid he up in the same. And Joseph laid up grain as the sand of the sea, very much, until they left off numbering; for it was without number" (Genesis 41, 48-49).   
The stores of wheat and barley served the inhabitants of Egypt during the period of drought and hunger that followed. But how did Joseph and the people of Egypt succeed in preventing pests from destroying the inventory they had accumulated, without any means of pest control and without being able to completely seal the storehouses? In order to answer that question, Prof. Mordechai Kislev, Dr. Orit Simhoni and Dr. Yoel Melamed from the laboratory for archaeological botany in the Life Sciences department of BIU used the burnt corpse of the beetle from the grain of wheat.
The beetle belongs to the Rhyzopertha dominica species, also known as the Lesser Grain Borer, one of three insects that are among the most important storehouse pests. These insects eat grain, but rather than doing so in the field, they prefer to wait until humans harvest the
wheat or barley and store it in a silo.
The lesser grain borer can cause a tremendous amount of damage. Each female lays between 300 and 500 eggs a month. In other words, one female can give birth to thousands of offspring in one year. The larvae of the grain borer eat wheat or barley. The pest can finish off a granary
within a very short time.
Fortunately, during the period when Joseph came to power in Egypt, the lesser grain borer was only beginning its migration westward. This insect originated in East Asia, in what is now India. It belongs to a family of insects whose larvae bore into trees. The larvae of the grain borer changed their taste several thousand years ago, when they began migrating westward, and since then they have preferred wheat and barley.
The beetle studied by Dr. Simhoni and her partners was found in one grain of wheat among several tens of thousands that were discovered in a dig at Tel Beit She'an, conducted by Prof. Amihai Mazar of the Hebrew University in Jerusalem. That granary was dated to the Middle Bronze Age II B, about the time when Joseph was in Egypt. Various tests indicated that the
beetle from Tel Beit She'an is among the most ancient ever found in the Land of Israel. So far, excavations have revealed only one other beetle from an earlier period. In other words, during that period the lesser grain borer was just beginning to spread in the Middle East.
Although their field of expertise is botany, the three researchers were familiar with granary pests from their previous study of grains found in Tel Hadar, on the shore of Lake Kinneret, north of Ein Gev. In the grain gathered at Tel Hadar they found a large number of such pests.
When they examined the vestiges of the plants in the granary at Tel Beit She'an, the three researchers came to the conclusion that the wheat had been harvested in the Gilead region. The conclusion reminded Prof. Kislev of the caravan of Ishmaelites that came from the Gilead, whose members bought Joseph from his brothers and took him with them to Egypt (Genesis 36, 25-28).
Joseph, thanks to his talent as an interpreter of dreams and his cleverness, quickly attained the rank of viceroy to the king and was appointed to run the kingdom's food storehouses. His success at the job was based not only on his talent for planning and his ability to see ahead, but also from the manner in which the pests spread. The lesser grain borer was just starting its career in Egypt when Joseph arrived there. Because of its phenomenal reproductive capacity, storing one batch of grain containing a small population of the grain borer was enough to bring about the destruction of the entire granary and to threaten an entire city with starvation.
Kislev, Simhoni and Melamed believe that Joseph was aware of this and therefore - according to the biblical description - he isolated the grain of each city in its own jurisdiction and prevented the transfer of batches of grain from one community to another. In their opinion,
that is the meaning of the verse: "and [he] laid up the food in the cities; the food of the field, which was round about every city."
In spite of the lack of chemical means of pest control, they add, it is also possible that those living in ancient Egypt were familiar with a simpler means of pest control. They learned this from an explanation of the story by Rashi, an 11th century biblical commentator. "And people put amongst the grain some of the earth of the place, and this prevents it from decaying," wrote Rashi.
According to the interpretation of the three researchers, Rashi was referring to a method by which fine sand is added to the grain. The grains of sand scratch the hard covering that surrounds the body of the beetle, and make it dry up and die. This method is still used today by various African tribes, and we can assume that it was sufficiently effective to exterminate a pest that had just arrived in the region, like the lesser grain borer.
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