One version of the story of Dr. Chapurukha (Chap) Kusimba's research can be found at The East African website:
Digging for history in the sands of time
by Rupi Mangat
Here are two key paragraphs from the article on discoveries made by Dr. Kusimba, an archaeologist with the Field Museum in Chicago, at the Mtwapa ruins along the coast of southern Kenya:
“This era [the Holocene] sees the bi-directional flow of cultural objects and foods through trade over wide regions of the world. l’m particularly interested in how domestic rice, coconuts, chickens and the Indian cow (Bos indicus) reached Africa from Asia and how African domestic foods like sorghum and millet reached Asia and became staples in countries there.”
This list of trade items shows that many of these exchanges of crops between Africa and South East Asia through trade happened as early as 4,000 years ago.
Now obviously these discoveries are greatly supportive of the theories of J. I. Miller, myself and others about the ancient age of the Cinnamon Route.
In an email correspondence with Dr. Kusimba, I was able to find out that it was specifically the sorghum and millet from the Africa to Asia; and citrus fruit, bananas and Indica rice from Southeast Asia to Africa, that date back to about 4000 years ago (1732 BCE).
Chickens, probably from Insular Southeast Asia, date back at Mtwapa to about 1000 BCE, and the coconut finds have not been datable so far.
Previously I have discussed how banana phytoliths dating back to 500 BCE have been found in Nigeria, and dating to about 2500 BCE were discovered in Munsa, Uganda. Banana cultivation is complicated and labor-intensive so there is no doubt that these domesticated plants were carried to Africa by humans.
Dr. Kusimba mentions that East Africa was known to the ancient Romans as the "Cinnamon coast," and I have suggested earlier, following Miller, that the ancient port known as Rhapta in Greek texts was probably the Punt of the ancient Egyptians. Rhapta was located in the same area as the bustling medieval island ports of Pemba and Zanzibar in modern-day Tanzania. Evidence of chickens in Tanzania dates back to 2800 BCE. These islands are actually quite close to the Mtwapa ruins, which are just north of Mombasa. Possibly we can say that Mtwapa was in the same economic zone as Rhapta, and we cannot rule out that Mtwapa may have been the actual site of that ancient port.
There is evidence of cinnamon or cassia that has been found in animal mummies dating back to the XXIII Egyptian dynasty (818-715 BCE) by Dr. Stephen Buckley. He also found traces of cinnamon or cassia that he states probably came from Southeast Asia in the canopic jar of Djediufankh, which is dated to about 664 - 525 BCE. Cinnamon has also been found at a Hera temple on the island of Samos in Greece that dates back to the 7th century BCE. This evidence puts to rest the idea that that the cinnamon of the ancients that traveled up the eastern African coast was not the cinnamon of Asia that we know today.
It is also worth mentioning again the discovery of clove flower buds at Terqa, Syria, at roughly the same time as the earliest dates for Mtwapa. These cloves may have followed a different coastal route, which I have called the Clove Route, as opposed to the probably trans-oceanic Cinnamon Route that bypassed most of the Asian coast.
Paul Kekai Manansala