The Acacia wars, resolved

In an at times acrimonious process (some have even called it a “wattle war”), the former plant genus Acacia has been split into five genera, with further splits likely. The XVIII International Botanical Congress in 2011 confirmed a previous decision to retain the Acacia name for the largest of the resulting genera, found mainly in Australia:

“Under the internationally accepted rules governing the correct naming of plants, the International Code of Botanical Nomenclature, the name would normally have remained with the African-American group, as this includes the species Acacia nilotica, which is the nomenclatural type species… However, a special provision of the Code allows for the name of the type species of a genus to be changed in cases like this, where strict application of the rules would require a large number of species to be renamed… An application under this provision was made in 2003… This was considered by the relevant botanical committees, who decided in its favour. The International Botanical Congress at Vienna in 2005 ratified this decision. The Vienna decision was contested by a group of botanists involved with African and American acacias. The Melbourne Congress, in two important votes on the first day of the Nomenclature Section, supported the procedure used in Vienna by a large majority. Support for this decision was widespread and not confined to Australian delegates. This vote effectively confirmed that the type species of Acacia is now an Australian species.”

The resulting division of the former Acacia is as follows:

The map below shows the distribution of the new genera, divided into the Americas, Africa, Asia, and Australia & the Pacific (background image from NASA Visible Earth). A degree of reorganisation was going to be needed whatever nomenclature proposal was accepted, but it certainly made sense to retain the Acacia name for 71% of the original species (although Wikipedia, which becomes more and more partisan as time passes, ran a campaign against the official decision for several years). The botanical community seems quite happy using the new names, and it does not seem that the issue will resurface at the XIX International Botanical Congress later this year, although there continues to be debate about how to resolve similar issues in the future.

Here are the five new genera, with examples:

Mariosousa

About 13 species, in the Americas. See theplantlist.org.


Mariosousa willardiana (Palo Blanco – photo: Tomas Castelazo)

Acaciella

About 15 species, in the Americas. See theplantlist.org.


Acaciella angustissima (photo: USDA)

Vachellia

About 163 species, throughout the tropics. See theplantlist.org.


Vachellia smallii (photo: Stan Shebs)

Senegalia

About 203 species, throughout the tropics. See theplantlist.org. This genus is likely to be split further.


Senegalia laeta (photo: Marco Schmidt)

Acacia

About 987 species, almost all in Australia and the Pacific.


Acacia pycnantha (Golden Wattle – photo: Melburnian)


World Solar Challenge: the board game!

Readers of this blog will know that I am passionate about science / technology / engineering / mathematics education, and that I am passionate about board games, and that I am passionate about solar car racing (with the ESC and the Sasol Solar Challenge coming up soon). Wouldn’t it be great if those three things could be combined?

Well, now they can! To assist solar car teams with education/outreach efforts, I’ve put together a simple board game based on the World Solar Challenge, and aimed mostly at kids. It looks like this:

The online game store (faciliated by the wonderful people at The Game Crafter) has a free download link for the rules, should anyone wish to take a look. I also have a few other educational games there.


Where are the European Solar Challenge teams from?

There will be 12 solar car teams competing in the European Solar Challenge this year. The map below shows where they are from (click to zoom). See here for more information about the teams.

The ESC will be held at Circuit Zolder in Belgium from September 23 to 25 this year. It will be a 24 hour endurance track race, competing against a (non-solar) Tesla Model S. About half the points for the ESC will come from the number of laps of the track completed. Other points will come from the fastest lap time, a timed chicane challenge on the 23rd, and a presentation about the car. Follow the race on Facebook and Twitter.


The Blue Mountains Water Skink


The endangered Blue Mountains Water Skink, Eulamprus leuraensis (photo: “Sarshag7”)

I have previously mentioned my interest in ecological niche modelling and amphibians. The cute little skink above, native to the Blue Mountains near Sydney, is sadly endangered. The black circles in the map below show online occurrence records for the skink. These range in altitude from approximately 530 to 1,170 m.

The blue area shows a predicted potential range for the species, based on MaxEnt modelling using those occurrence records and BioClim climate data. The model does not take into account the skink’s need for sedge and shrub swamps with permanently wet boggy soils – there are readily available online land cover datasets, but these have insufficient spatial resolution to identify the 30 or so swamps in which the skink is found. The predicted potential range for the skink is consequently very much exaggerated, and covers 1,320 sq km, of which 63% falls within national parks or other protected areas. Hopefully that is enough to stop this beautiful amphibian from becoming extinct, although it continues to face threats from urban sprawl, feral cats, and vegetation changes.


Social media around the world

Sticking with the social media theme of my last post, here is a nice pair of maps by social media guru Vincenzo Cosenza of the most popular and 2nd most popular social media platform by country:


For much of the world, including Australia and the USA, it’s Facebook followed by Instagram (although the Sensis Social Media Report suggested that LinkedIn actually comes second in Australia). China has Qzone on top, while VK and Odnoklassniki are big in the former USSR, and Facenama is big in Iran. Orkut, once hugely popular in some countries, has of course been closed down.