For my August 2012 diary, go here.

Diary - September 2012

John Baez

September 1, 2012

September 2, 2012

This is Felis silvestris: a species of wild cat from which the house cat Felis catus descends. In fact they interbreed, so some argue they should count as the same species, but the wild ones are bigger.

Felis silvestris seems to have appeared in Europe about 2 million years ago. Around 50,000 years ago it migrated from Europe to the Middle East, giving rise to some subspecies called steppe wildcats. Steppe wildcats then spread into Asia and Africa. Felis silvestris reached the British Isles from mainland Europe 9000 years ago, at the end of the last ice age, before rising sea levels created the British Channel.

Felis silvestris in turn descended from Felis lunensis, or Martelli's wildcat, which appeared in Europe around the end of the Pliocene and beginning of the Pleistocene, 2.5 million year ago. It would be cool if we could use genetic engineering to recreate Martelli's wildcat and even earlier kinds of cats. But there are also lots of wild cat species alive today, some on the brink of extinction, which deserve to be saved.

September 3, 2012

This cat named Venus is a 'chimera': it has two sets of genes. In a sense, it is its own fraternal twin:

A chimera is typically formed from four parent cells (either two fertilized eggs, or two early embryos that have fused together). When the organism forms, the cells that had already begun to develop in the separate embryos keep their original phenotypes and appearances. This means that the resulting animal is a mixture of tissues and can look like this gorgeous (but bizarre) kitty.

September 10, 2012

An infinity of foods for an infinity of ghosts!

At the Buddha Tooth Relic Temple in Singapore, we recently saw these tables set up for the Hungry Ghost Festival. It happens in the middle of the 7th lunar month, Ghost Month, when the gates of hell are opened and ghosts are free to roam the earth, where they seek food and entertainment. Hungry ghosts are ancestors of people who neglected to give them a proper funeral or pay tribute to them after they died.

September 14, 2012



Lisa and I had dinner on Keppel Island, off the south shore of Singapore. We took a walk got a great view of the mangrove forests and the strange towers on the mainland directly to the north.





For my October 2012 diary, go here.


© 2012 John Baez
baez@math.removethis.ucr.andthis.edu

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