Bamboo has a log
evolutionary history and the fact that both gorillas and Pandas rely on them
for food is impressive. That the
separate linages go back to Gowanda land is also remarkable. These plants have been with us for a long
time and now been human friendly are clearly ending up almost everywhere.
Bamboo needs the
full press of industrial design and tooling applied to it as a natural
feedstock. That is coming as we work
harder to get of the oil shortcut. Bur
it will still take time and individual tinkering.
All good.
Out of Africa?
New bamboo genera, mountain gorillas, and the origins of China's bamboos
by Staff Writers
Washington DC (SPX) Aug 26, 2013
Bergbambos tessellata is a clump-forming bamboo with
ragged leaves and sheaths found in dry areas of southern Africa especially the
Drakensberg Mountains. Credit: Chris Stapleton.
African mountain bamboos are something of a mystery,
as nearly all bamboos are found in Asia or South America. Hidden away up
mountains in the tropics where they provide food for gorillas, just as China's
bamboos provide food for the Giant Panda, there are apparently only 2 species,
and they had not been examined in very great detail, except by the gorillas.
It had been thought that they were very closely
related to the hundreds of similar bamboos in Asia, but their respective ranges
are separated by thousands of miles.
As flowering in bamboos is such a rare event,
spreading by seed takes a very long time, and the suspicion arose that they
might be old enough to represent new genera, and possibly could even be
remnants of the earliest temperate bamboos, which spread to Asia on drifting
tectonic plates. A new study published in the open access journal PhytoKeys,
studies the diversity and evolution of African bamboo.
Having studied bamboos in the Himalayas extensively,
and edited the descriptions of all the bamboos of China for the Flora of China
Project of Academia Sinica and Missouri Botanical Gardens, Dr Chris Stapleton
turned his attention to the bamboos of Africa.
He found that the features of the mountain bamboos
were significantly different to those of Asia, and together with the large
geographic separation, the differences were sufficient for the recognition of 2
new African genera, now named Bergbambos and Oldeania, after their local names
in the Afrikaans and Maasai languages.
The species are now Bergbambos tessellata and
Oldeania alpina.
DNA had been extracted from these bamboos and
examined on several occasions, but the results of analyses were variable and
could not prove a close relationship to any of the bamboos of Asia. What is
clear when looking at all the DNA results together is that the African bamboos
represent two separate lineages, and neither can be included in any known Asian
genus.
Earlier work on the global distribution of bamboos
has shown that bamboos evolved in the southern hemisphere on a landmass called
Gondwanaland, parts of which spread apart to form South America, Africa and
Asia when it broke up as a result of continental drift, the slow movement of
tectonic plates on the earth's surface.
The incredible variety of temperate bamboos in China
is thought to be a result of the early bamboos spreading out from either Africa
or India when the plates collided and allowed the hitch-hiking bamboos to jump
across into new territory.
The features and DNA of the African bamboos are
certainly different to those of East Asia, but it is still not clear whether
they are really different enough to represent ancestors of all the Asian
bamboos.
It will be necessary to hunt out and study mountain
bamboos of Sri Lanka and Madagascar and to include them in a broader analysis
to be sure. From this review, however, it looks as though African bamboos
evolved about the same time as the bamboos of E Asia.
The miriad temperate bamboos of China are more
likely to have been a gift from India, rather than another 'Out of Africa'
story, but further work is needed to be sure. What is clear is that Africa has
two more endemic genera, and the bamboos are seen to be as unique as the
animals that depend upon them.
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