LIVING FOSSIL: Did you know that Ginkgo biloba is the only species remaining of a genus dating back 270 million years to the Permian era (before the time of dinosaurs)? Once widespread, they shrank in distribution around 2 million years ago to a tiny area of central China. Originally thought to be extinct, there is speculation that the existing trees were planted and preserved by Chinese monks over thousands of years, because they are genetically so uniform. Extremely slow growing, some trees are >2,000 years old.
• Ginkgo evolved before flowering plants. There are separate male and female trees. The female has “naked” ovules (hence the term gymnosperm). Pollen deposited on the ovules contains motile sperm armed with thousands of flagella. The seed that develops contains butanoic acid, which gives it the smell of butter (unfortunately, rancid butter) and caproic acid which has been charmingly likened to “old gym socks”. Despite this, they are cooked into congee and Buddha’s Delight. Thought to have aphrodisiac qualities, the seeds contain ginkgotoxin that can cause seizures.
More images/videos on this site: http://kwanten.home.xs4all.nl/ovule.htm
I liked this 5 minute video, in Japanese, showing swimming sperm: http://cgi2.nhk.or.jp/school/movie/bangumi.cgi?das_id=D0005100132_00000
• Ginkgo extracts are thought to have memory boosting and anti-dementia properties from flavonoid glycosides and terpenoids. Clinical trials, unfortunately, show conflicting results. See Wiki for a summary: http://en.wikipedia.org/wiki/Ginkgo_biloba
IMAGE: Kevin Staff made this lovely companion gif to accompany the networked leaf on the You’re So Vein post. Note that the ancient Ginkgo leaf is susceptible to damage in the central vein as seen by the block in fluorescent dye flow. Contrast this to the more evolved modern leaf with its efficient, recursively looped network (http://goo.gl/Xz8iT).
Early submission for ScienceSunday curated this weekend by Robby Bowles , Chad Haney and special guest curator Rich Pollett while I am traveling.