Fungus suckers

The plant family Burmanniaceae is a long-standing botanical heartthrob (#Botanicalheartthrob) of mine. Ghost-like obligate parasites, bound by their evolutionary heritage to a strange existence amongst the fallen debris that litters a forest floor, the Burmaniaceae feed on fungus.

 

 

The condition of this odd plant variety is called mycoheterotrophism. It’s a parasitic relationship between certain plants and fungi, where the plant derives some, if not all, of it’s food by parasitising the fungus.

That’s right. Instead of feeding on sunlight like good old regular plants, mycoheterotrophs feed on fungus. Cheaters.

Amazingly, many of the Burmanniaceae have completely lost their ability to photosynthesise. They are achlorophyllous (pronounced ‘ay-cloro-fi-lus’), meaning they have no chlorophyll; the cellular centres for converting harvested sunlight into sugars that feed the plant.

No chlorophyll at all folks. That’s like being an animal without a stomach. Oh wait…

 

 

The habit of plants deriving nutrition from fungus has evolved several times independently, including in both monocots and eudicots, and is most prolifically represented in each clade amongst the Orchidaceae (orchids) and Ericaceae (e.g. Epacris impressa, the stunning floral emblem of Victoria). Similarly, it is likely that the extreme, obligate fungus-sucking habit–necessitated by a complete evolutionary loss of chlorophyll–has arisen several times independently within the Burmanniaceae family alone (Merckx et al. 2008). Burmanniaceae’s mycoheterotrophism is, therefore, considered an adaptation to deal with dank, dark, low light conditions that persist on the forest floor (Bidartondo et al. 2004).

Unaware of this diversity, and being the first fungus-sucking plants I had encountered, Burmaniaceae instantly captured my imagination. Too many zombie films, perhaps, but also a novel insight into the oddities of natural selection.

 

 

There is considerable conflicting information available on the number of genera and species within the family Burmanniaceae. Listings range from between seven and seventeen genera, and 95 to 159 species (see also Merckx et al. 2006). It is unclear whether this issue is due to conflicting opinions on synonymous species (where some botanists believe two differently named species constitute one and the same), synonymy of the families Burmanniaceae and Thismiaceae, or outdated information on a number of online databases and in the literature.

“…eking out what appears a rather diminished and utterly fragile existence for a traditionally photosynethic organism…”

According to the APG IV system (Angiosperm Phylogeny Group: APG IV 2016), a modern, mostly molecular-based system of classifying flowering plants, there are eight genera in the Burmanniaceae family, comprising some 96 species of fungus-sucking plants.

The biggest of these genera, Burmannia, includes roughly two thirds of these species, and is spread across tropical and subtropical parts of Africa, Oceania and the Western Hemisphere. The next largest genus is Gymnosiphon, comprising 24 species across the Old and New World tropics, but the remaining genera are far less speciated; Apteria (3 species, tropical and subtropical America), Dictyostega (1 species, Mexico and Brazil), Marthella (1 species, Trinidad), and four genera native to tropical S. America, including Campylosiphon (1 species), Cymbocarpa (2 species), Hexapterella (2 species) and Miersiella (1 species).

 

 

In Australia, Burmanniaceae is represented by just two native speciesBurmannia juncea (above left), native to Northern Australia (swampy areas, streamsides and wetlands), and Burmannia disticha, native to the east coast of NSW and QLD (swamps and wetlands in coastal regions). According to the Atlas of Living Australia, a community science database on the continent’s flora and fauna, the southeast Asian B. coelestis (Zhang & Saunders 2000) also occurs across far northern Australia.

Despite eking out what appears a rather diminished and utterly fragile existence for a traditionally photosynethic organism, these little creeps, at least in Australia, are considered not threatened and of least conservation concern.

Good job zombie herbs. Keep on keeping on.

 

References

Online references are linked to via in-text hyperlinks.

APG IV (2016) An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV. Botanical Journal of the Linnean Society 181 (1): 1–20. doi:10.1111/boj.12385.

Bidartondo M. I., Burghardt B., Gebauer G., Bruns T. D. & Read D. J. (2004) Changing partners in the dark: isotopic and molecular evidence of ectomycorrhizal liaisons between forest orchids and trees. Proceedings of the Royal Society of London B 271: 1799–1806.

Merckx V., Chatrou L., Lemaire B., Sainge M., Huysmans S. & Smets E. (2008) Diversification of myco-heterotrophic angio- sperms: evidence from Burmanniaceae. BMC Evolutionary Biology 8: 178.

Merckx V., Schols P., Kamer H. M.-V. D., Maas P., Huysmans S. & Smets E. (2006) Phylogeny and evolution of Burmanniaceae (Dioscoreales) based on nuclear and mitochondrial data. American Journal of Botany 93: 1684–1698.

Morton, J.B., Walker, C. (1984) Glomus diaphanum: A new species in the Endogonaceae common in West Virginia. Mycotaxon 21: 431-440.Zhang D. & Saunders R. M. K. (2000) Systematics of the Burmannia coelestis complex (Burmanniaceae). Nordic Journal of Botany 20: 385–394.

Images are presented unaltered from the original source and were: freely available under creative commons, or; were free for non-commercial sharing with appropriate attribution given (e.g. see here, but links to the originals are provided in each case, wherein the licensing particulars for each image can be found), or; were provided with direct permission from the author (Mac H. Alford Nodding-nixie photograph). Details of authorship can be found in each picture caption. 

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Best space day ever

As many of you know, I have the special privilege of working as a science educator at the Victorian Space Science Centre (VSSEC), Strathmore, Victoria. VSSEC’s flagship program for young teenagers, loosely based on the Space Camp program, Alabama (watch this for a run down), is the Mission to Mars; a simulation of humankind’s soon-to-be first landing on our neighbouring planet.

 

 

This stellar, fully-interactive Mission to Mars program sends half the student group to mission control, while the other half are landed on Mars as a team of scientist and engineer astronauts. The astronauts conduct experiments, monitor weather readings and collect samples on a simulated Martian surface, while their mission controllers direct them in their endeavours, problem solving and negotiating the astronauts through technical malfunctions and martian dangers to bring their people safely home.

 

 

Uniquely, we had the pleasure last week of running a Mission to Mars for The Australasian Society of Aerospace Medicine (ASAM). These visitors were somewhat different to the 13 through 15 year-old astronauts we usually unleash on Mars. These ASAM visitors were a collective of highly skilled pilots, engineers, psychologists, biomedical scientists and educators.

The whole day was a huge buzz; alive with exciting discussions about humans in space, the potential of life on Mars, and what our motivations for exploring that planet should be.

Among these discussions and meetings, however, there was a particular stand out for me. I got to chat with Mars One candidate Dianne McGrath.

Her eyes are firmly fixed on the skies, but not for the reasons one might expect. You see, Dianne McGrath is motivated by her insight into humanities urgent need to extend our sustainable practices. As she explained to me, Mars One provides an opportunity to model the behaviour she wants to see us humans take down here on solid ground; complete sustainability in water, energy, food and waste. There is simply no other choice in the Martian habitat.

For real time insights into student-led space and Mars programs, follow @VSSEC@SpaceCampUSA and @TheMarsGen on Twitter, or check out their websites (in-text) for program information.

 

Mission to Mars photos courtesy of Marc Jurblum @mars_psych, used with permission. 

A huge thanks to Rabbot Hutch, the inquisitive man behind the camera, genuinely amazing artist, dog owner and housemate extraordinaire. Follow him @rabbothutch on insta.

Follow pug Thor @Thormypug on insta.

Best space day ever goes out to Nicole Morton, the most aspiring and inspiring woman I am lucky enough to call my friend.

 

 

Part 3: First Humans

On a hilltop in the Sahara Desert (Morocco, far northern Africa), at a retired mining site called Jebel Irhoud, a group of paleoanthropologists recently changed the course of history.

The team was led by one Jean-Jacques Hublin, a paleoanthropologist from the Max Planck Institute for Evolutionary Anthropology, Germany. The story of Jebel Irhoud kicked off in the 1960’s, when baryte mining operations at the site uncovered some pretty amazing, then-dubbed pre-human artefacts.

Starting in 1961, myriad stone tools and hominid fossils were uncovered after an on-site miner discovered what would later be identified as a hominid skull; ‘hominid‘ being the group that comprises all modern and extinct Great Apes–feat. humans–as well as all their immediate ancestors. This miner, presumably somewhat but not entirely unaware of the value of this piece, gifted the skull to an engineer who then held on to the artefact as a souvenir. Eventually, the skull was relinquished to the University of Rabat, Morocco, leading to the first paleontological expedition to Jebel Irhoud in 1961.

On account of the work carried out during this expedition, the Jebel Irhoud site was first falsely dated to just 40,000 years ago. As such, and because of the stone tools present that were historically associated with ancient relatives of us modern humans, the Moroccan hominid fossils from Jebel Irhoud were originally attributed to Neanderthal; a ‘sister species’ of Homo sapiens thought to have evolved directly from Homo erectus alongside us modern humans.

Re-enter Jean-Jacques Hublin.

Following on some forty years later, starting in 2004, Hublin’s group revisited Jebel Irhoud. To say the least, he is a little modest about the work they carried out there…

“We were very lucky,” Hublin says. “We didn’t just get dates, we got more hominids.”

Hublin’s team got a lot more hominids, but the most exciting finding was the spectacularly older date they calculated for the Jebel Irhoud site: a brand-spanking 300,000 years.

They also reexamined the hominid remains, and attributed them to Homo sapiens, rather than Neanderthals, making these the oldest known record of the modern human race. In doing so, Hublin’s team pushed the world’s start date for our species back by almost 100,000 years.

Furthermore, “artifacts found with the fossils suggest that activities typical of modern humans also emerged by 300,000 years ago”, says paleoanthropologist Alison Brooks, George Washington University. It also evidences a “a lot of communication across the continent,” Brooks says, “a  pan-African phenomenon, with people expanding and contracting across the continent for a long time.”

Just listen to Hublin explain the significance of this pan-African phenomenon.

 

 

See Part 1: Jane Goodall and Part 2: The Leakey Legacy for a good ol’ fashioned, well-rounded look at the events and reading that brought me to this story in the first place.

The original article, Hublin et al. (2017) “New fossils from Jebel Irhoud, Morocco and thpan-African origin of Homo sapiens”, published in Nature 546 can be found here.

All other references linked to in-text.

 

 

Part 2: The Leakey Legacy

Jane Goodall’s early work on chimpanzees was solicited by paleoanthropologist and archaeologist Louis Leakey (pictured with her above), who believed the study of primates to be pivotal to an understanding of the early evolution of humans. Having facilitated Goodall’s scientific blossoming (see Part 1: Jane Goodall), in his own right Louis Leakey is an enduring, iconic figure in paleoanthropology. 

Here enters the Leakey family.

Born in 1903, Louis Leakey spent most of his life married to and working in collaboration with his second wife, Mary Leakey (paleontologist). Together, they raised three sons, including the paleoanthropologist to-be Richard Leakey.

“Louis Leakey led what can only be described as a life fit for fiction. Think Indiana Jones, and you’re on the right track.”

Throughout their long careers, all three paleo-inclined members of the Leakey family uncovered anthropological artefacts that have continued to serve as essential, illustrative pieces in the narrative we now tell on the evolution of our species. These artefacts, stone stools and pre-human and Homo fossil remains, were essential to the scientific epiphany that early humans evolved in Africa.

 

 

 

First man to the family, Louis Leakey was also the first in his science to prescribe multiple, concurrent lines of evolution within our ancestral history (rather than a single evolutionary chain of a -> b -> c -type transitions). He was also the first to argue fiercely for Africa as the ‘cradle of humanity’, an assertion further evidenced by the work of Mary and Richard Leakey, and one that has truly stood the test of time.

Amongst Louis Leakey’s academic acclaim–the publication of some 20 books and over 150 scientific articles in his time–Louis Leakey led what can only be described as a life fit for fiction. Think Indiana Jones, and you’re on the right track.

Time for the ‘adventure highlights tour’ of father and son.

Having grown up speaking Kukuyu (the language and name of the largest ethnic group in Kenya) as fluently as English, Louis Leakey was initiated as a tribe member in his teenage years. As a grown man, dispute over the veracity of some of Louis’s research claims led to his being ousted from Cambridge in 1935, and living in veritable poverty for some 18 months thereafter. This was due to some serious academic misfortunes, including compromised photographic film and the removal of research site markers by local tribesman for use as harpoons. In 1939,  he was drafted by the Kenyan government as an intelligence policeman.

Louis also involved himself, carefully, in the politics of the country; namely between the Kukuyu and white colonialists. At one stage between 1949-52, he was placed under 24-hr government guard against the Mau Mau, a guerrilla organisation of Kikuyu, the largest ethnic group in Kenya, which was striking out against the resident European settlers, but he also wrote extensively in defence of the Kukuyu’s rights. He also famously debated the ethics of female genital cutting with Jomo Kenyatta, who later became a president of Kenya, and he conducted the first Pan-African Congress of Prehistory. 

Richard Leakey, son to Louis Leakey, lived a similarly adventure-ridden life. Growing up in Nairobi, his major endeavour as a teenager was in trapping and skeleton supply; utilising his skills on horseback and as a Land Rover mechanic. As a young adult in 1967, on an expedition to excavate fossils along the Omo river, his boat was attacked by crocodiles. The contingent of onboard workers barely escaped with their lives. In 1993, Richard had his legs crushed in a plane crash wherein sabotage was suspected, but never proven. And, as the first chairman of the Kenyan Wildlife Service, he created armed anti-poaching units that were authorised to kill poachers on site.

These guys were 20th century badass.

And their legacy continues today, in a big way. See Part 3: First Humans, and check out the Leakey Foundation’s Origin Stories podcast to find out how.

 

Sources

The Leakey Foundation website, accessed 13/07/17. https://leakeyfoundation.org/about/the-leakey-family/

https://en.wikipedia.org/wiki/Louis_Leakey

https://en.wikipedia.org/wiki/Mary_Leakey

https://en.wikipedia.org/wiki/Richard_Leakey

Full family tree available at https://en.wikipedia.org/wiki/Leakey_family

Part 1: Jane Goodall

Jane Goodall is an incredible woman. A force to be reckoned with. She has a rare tenacity and a fierce sense of personal responsibility for her impact on the planet. In her own words:

“What you do makes a difference, and you have to decide what kind of difference you want to make.”

This year, Think Inc. delivered an Australia wide tour in collaboration with the Jane Goodall Institute; a ‘fire side’ chat with the woman herself, fronted up by a casual talk from Jane. I attended the Melbourne event at the Plenary on June 16th, where Jane Goodall told of her childhood fascinations with animals, the unfolding of her dream to work with animals in Africa, and spoke on her now long history of global activism.

This is a woman who worked crappy secretarial and hospitality jobs to scrape together enough pennies for the boat ride from England, around the Cape of Africa, on to Nairobi. A woman who essentially pioneered the field of animal behavioural science, in spite of being badly ridiculed by much of the scientific community. And a passionate activist that admits she has not been in the same place for more than two or three consecutive weeks for some 30 years.

Jane Goodall’s personal story brings together true anthropological discovery, which is still unfolding today (see Part 3: First Humans)–but which had more of a wild west-type twang through the course of the C20th (see Part 2: The Leakey Legacy)–with pressing modern day issues: environmental degradation, overconsumption and human desperation in the developing world.

In writing this three-piece blog series I came to realise that, in truth, there is little I can say to elucidate Jane Goodall’s work, insight and ferocity that she does not immediately demonstrate herself. Just watch her.

 

 

To end on a moral note as Goodall did herself, the crux of Jane’s fear for the world seems to be this; in spite of the undeniable evidence for human-induced climate change, in spite of the devastating degradation of natural habitats carried out by our species, so many of us continue to do nothing. And as she emphasises, our time to make a difference is already on the clock.

“The greatest danger to our future is apathy,” she says.

Since attending Jane’s Think Inc. talk, I have started to realise how often the children and teenagers I meet through my education and science communication work have already adopted, at their fledgling age, a wholly hopeless outlook on our planets future.

I, myself, am wholeheartedly committed to realism but, as Jane clearly indicates herself, we need, absolutely, to remain optimistic. In fact, our future depends on it.

“You would be amazed at what inspired children can do.” – Goodall

 

Information on the Roots & Shoots program referred to at the end of this video can be found here, with some 23 schools participating in Victoria alone at the time of writing.

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