Tag Archives: conservation

Taxonomies (classification schemes) rouse passions

There seems to have been some lively debate among biologists about matters most of us treat as invisible: naming, establishing, and classifying categories. These activities can become quite visible when learning a new language, e.g., French which divides nouns into two genders or German which classifies nouns with any of three genders.

A July 26, 2020 essay by Stephen Garnett (Professor of Conservation and Sustainable Livelihoods, Charles Darwin University, Australia), Les Christidis (Professor, Southern Cross University, Australia), Richard L. Pyle (Associate lecturer, University of Hawaii, US), and Scott Thomson (Research associate, Universidade de São Paulo, Brazil) for The Conversation (also on phys.org but published July 27, 2020) describes a very heated debate over taxonomy,

Taxonomy, or the naming of species, is the foundation of modern biology. It might sound like a fairly straightforward exercise, but in fact it’s complicated and often controversial.

Why? Because there’s no one agreed list of all the world’s species. Competing lists exist for organisms such as mammals and birds, while other less well-known groups have none. And there are more than 30 definitions of what constitutes a species [emphasis mine]. This can make life difficult for biodiversity researchers and those working in areas such as conservation, biosecurity and regulation of the wildlife trade.

In the past few years, a public debate erupted among global taxonomists, including those who authored and contributed to this article, about whether the rules of taxonomy should be changed. Strongly worded ripostes were exchanged. A comparison to Stalin [emphasis mine] was floated.

Here’s how it started,

In May 2017 two of the authors, Stephen Garnett and Les Christidis, published an article in Nature. They argued taxonomy needed rules around what should be called a species, because currently there are none. They wrote:

” … for a discipline aiming to impose order on the natural world, taxonomy (the classification of complex organisms) is remarkably anarchic […] There is reasonable agreement among taxonomists that a species should represent a distinct evolutionary lineage. But there is none about how a lineage should be defined.

‘Species’ are often created or dismissed arbitrarily, according to the individual taxonomist’s adherence to one of at least 30 definitions. Crucially, there is no global oversight of taxonomic decisions — researchers can ‘split or lump’ species with no consideration of the consequences.”

Garnett and Christidis proposed that any changes to the taxonomy of complex organisms be overseen by the highest body in the global governance of biology, the International Union of Biological Sciences (IUBS), which would “restrict […] freedom of taxonomic action.”

… critics rejected the description of taxonomy as “anarchic”. In fact, they argued there are detailed rules around the naming of species administered by groups such as the International Commission on Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants. For 125 years, the codes have been almost universally adopted by scientists.

So in March 2018, 183 researchers – led by Scott Thomson and Richard Pyle – wrote an animated response to the Nature article, published in PLoS Biology [PLoS is Public Library of Science; it is an open access journal].

They wrote that Garnett and Christidis’ IUBS proposal was “flawed in terms of scientific integrity […] but is also untenable in practice”. They argued:

“Through taxonomic research, our understanding of biodiversity and classifications of living organisms will continue to progress. Any system that restricts such progress runs counter to basic scientific principles, which rely on peer review and subsequent acceptance or rejection by the community, rather than third-party regulation.”

In a separate paper, another group of taxonomists accused Garnett and Christidis of trying to suppress freedom of scientific thought, likening them to Stalin’s science advisor Trofim Lysenko.

The various parties did come together,

We hope by 2030, a scientific debate that began with claims of anarchy might lead to a clear governance system – and finally, the world’s first endorsed global list of species.

As for how they got to a “clear governance system”, there’s the rest of the July 26, 2020 essay on The Conversation or there’s the copy on phys.org (published July 27, 2020).

The Broad Institute gives us another reason to love CRISPR

More and more, this resembles a public relations campaign. First, CRISPR (clustered regularly interspersed short palindromic repeats) gene editing is going to be helpful with COVID-19 and now it can help us to deal with conservation issues. (See my May 26, 2020 posting about the latest CRISPR doings as of May 7, 2020; included is a brief description of the patent dispute between Broad Institute and UC Berkeley and musings about a public relations campaign.)

A May 21, 2020 news item on ScienceDaily announces how CRISPR could be useful for conservation,

The gene-editing technology CRISPR has been used for a variety of agricultural and public health purposes — from growing disease-resistant crops to, more recently, a diagnostic test for the virus that causes COVID-19. Now a study involving fish that look nearly identical to the endangered Delta smelt finds that CRISPR can be a conservation and resource management tool, as well. The researchers think its ability to rapidly detect and differentiate among species could revolutionize environmental monitoring.

Caption: Longfin smelt can be difficult to differentiate from endangered Delta smelt. Here, a longfin smelt is swabbed for genetic identification through a CRISPR tool called SHERLOCK. Credit: Alisha Goodbla/UC Davis

A May 21, 2020 University of California at Davis (UC Davis) news release (also on EurekAlert) by Kat Kerlin, which originated the news item, provides more detail (Note: A link has been removed),

The study, published in the journal Molecular Ecology Resources, was led by scientists at the University of California, Davis, and the California Department of Water Resources in collaboration with MIT Broad Institute [emphasis mine].

As a proof of concept, it found that the CRISPR-based detection platform SHERLOCK (Specific High-sensitivity Enzymatic Reporter Unlocking) [emphasis mine] was able to genetically distinguish threatened fish species from similar-looking nonnative species in nearly real time, with no need to extract DNA.

“CRISPR can do a lot more than edit genomes,” said co-author Andrea Schreier, an adjunct assistant professor in the UC Davis animal science department. “It can be used for some really cool ecological applications, and we’re just now exploring that.”

WHEN GETTING IT WRONG IS A BIG DEAL

The scientists focused on three fish species of management concern in the San Francisco Estuary: the U.S. threatened and California endangered Delta smelt, the California threatened longfin smelt and the nonnative wakasagi. These three species are notoriously difficult to visually identify, particularly in their younger stages.

Hundreds of thousands of Delta smelt once lived in the Sacramento-San Joaquin Delta before the population crashed in the 1980s. Only a few thousand are estimated to remain in the wild.

“When you’re trying to identify an endangered species, getting it wrong is a big deal,” said lead author Melinda Baerwald, a project scientist at UC Davis at the time the study was conceived and currently an environmental program manager with California Department of Water Resources.

For example, state and federal water pumping projects have to reduce water exports if enough endangered species, like Delta smelt or winter-run chinook salmon, get sucked into the pumps. Rapid identification makes real-time decision making about water operations feasible.

FROM HOURS TO MINUTES

Typically to accurately identify the species, researchers rub a swab over the fish to collect a mucus sample or take a fin clip for a tissue sample. Then they drive or ship it to a lab for a genetic identification test and await the results. Not counting travel time, that can take, at best, about four hours.

SHERLOCK shortens this process from hours to minutes. Researchers can identify the species within about 20 minutes, at remote locations, noninvasively, with no specialized lab equipment. Instead, they use either a handheld fluorescence reader or a flow strip that works much like a pregnancy test — a band on the strip shows if the target species is present.

“Anyone working anywhere could use this tool to quickly come up with a species identification,” Schreier said.

OTHER CRYPTIC CRITTERS

While the three fish species were the only animals tested for this study, the researchers expect the method could be used for other species, though more research is needed to confirm. If so, this sort of onsite, real-time capability may be useful for confirming species at crime scenes, in the animal trade at border crossings, for monitoring poaching, and for other animal and human health applications.

“There are a lot of cryptic species we can’t accurately identify with our naked eye,” Baerwald said. “Our partners at MIT are really interested in pathogen detection for humans. We’re interested in pathogen detection for animals as well as using the tool for other conservation issues.”

Here’s a link to and a citation for the paper,

Rapid and accurate species identification for ecological studies and monitoring using CRISPR‐based SHERLOCK by Melinda R. Baerwald, Alisha M. Goodbla, Raman P. Nagarajan, Jonathan S. Gootenberg, Omar O. Abudayyeh, Feng Zhang, Andrea D. Schreier. Molecular Ecology Resources https://doi.org/10.1111/1755-0998.13186 First published: 12 May 2020

This paper is behind a paywall.

The business of CRISPR

SHERLOCK™, is a trademark for what Sherlock Biosciences calls one of its engineering biology platforms. From the Sherlock Biosciences Technology webpage,

What is SHERLOCK™?

SHERLOCK is an evolution of CRISPR technology, which others use to make precise edits in genetic code. SHERLOCK can detect the unique genetic fingerprints of virtually any DNA or RNA sequence in any organism or pathogen. Developed by our founders and licensed exclusively from the Broad Institute, SHERLOCK is a method for single molecule detection of nucleic acid targets and stands for Specific High Sensitivity Enzymatic Reporter unLOCKing. It works by amplifying genetic sequences and programming a CRISPR molecule to detect the presence of a specific genetic signature in a sample, which can also be quantified. When it finds those signatures, the CRISPR enzyme is activated and releases a robust signal. This signal can be adapted to work on a simple paper strip test, in laboratory equipment, or to provide an electrochemical readout that can be read with a mobile phone.

However, things get a little more confusing when you look at the Broad Institute’s Developing Diagnostics and Treatments webpage,

Ensuring the SHERLOCK diagnostic platform is easily accessible, especially in the developing world, where the need for inexpensive, reliable, field-based diagnostics is the most urgent

SHERLOCK (Specific High-sensitivity Enzymatic Reporter unLOCKing) is a CRISPR-based diagnostic tool that is rapid, inexpensive, and highly sensitive, with the potential to have a transformative effect on research and global public health. The SHERLOCK platform can detect viruses, bacteria, or other targets in clinical samples such as urine or blood, and reveal results on a paper strip — without the need for extensive specialized equipment. This technology could potentially be used to aid the response to infectious disease outbreaks, monitor antibiotic resistance, detect cancer, and more. SHERLOCK tools are freely available [emphasis mine] for academic research worldwide, and the Broad Institute’s licensing framework [emphasis mine] ensures that the SHERLOCK diagnostic platform is easily accessible in the developing world, where inexpensive, reliable, field-based diagnostics are urgently needed.

Here’s what I suspect. as stated, the Broad Institute has free SHERLOCK licenses for academic institutions and not-for-profit organizations but Sherlock Biosciences, a Broad Institute spinoff company, is for-profit and has trademarked SHERLOCK for commercial purposes.

Final thoughts

This looks like a relatively subtle campaign to influence public perceptions. Genetic modification or genetic engineering as exemplified by the CRISPR gene editing technique is a force for the good of all. It will help us in our hour of need (COVID-19 pandemic) and it can help us save various species and better manage our resources.

This contrasts greatly with the publicity generated by the CRISPR twins situation where a scientist claimed to have successfully edited the germline for twins, Lulu and Nana. This was done despite a voluntary, worldwide moratorium on germline editing of viable embryos. (Search the terms [either here or on a standard search engine] ‘CRISPR twins’, ‘Lulu and Nana’, and/or ‘He Jiankui’ for details about the scandal.

In addition to presenting CRISPR as beneficial in the short term rather than the distant future, this publicity also subtly positions the Broad Institute as CRISPR’s owner.

Or, maybe I’m wrong. Regardless, I’m watching.

Damage-free art authentication and spatially offset Raman spectroscopy (SORS)

In a world where people will shell out millions of dollars for a single painting, art authentication of some kind is mandatory from a buyer’s perspective while sellers might be a little more reluctant. Reliance on experts who have an intimate familiarity with an artist’s body of work, personal and professional history, as well as, the historical period in which the work was created is the norm. Technological means are not necessarily as heavily employed as one might expect. Given that most technical analyses require damage of some kind, no matter how miniscule, some reluctance is understandable.

A May 29, 2014 news item on phys.org describes a new, damage-free, art conservation and restoration process (which could easily be used for authentication purposes),

UK scientists, working on an international project to conserve precious works of art, have found a new way to analyse paintings without having to remove even a tiny speck of the paint to inspect the layers below.

Using laser spectroscopy, a method that uses light to probe under the surface of an object, the international team has developed a new, non-invasive way to identify the chemical content of the paint layers present.

This new technique will reduce the risk of damage to precious paintings, often worth thousands or even millions of pounds, when conservation and restoration work is being carried out.

Using laser spectroscopy, a method that uses light to probe under the surface of an object, the international team has developed a new, non-invasive way to identify the chemical content of the paint layers present.

This new technique will reduce the risk of damage to precious paintings, often worth thousands or even millions of pounds, when conservation and restoration work is being carried out.

Read more at: http://phys.org/news/2014-05-lasers-analyse-priceless-art.html#jCp

As noted in a March 24, 2014 posting about using surface-enhanced Raman spectroscopy (SERS) to determine the characteristics of red pigment in a Renoir painting, restoration, authentication, and conservation are all linked once researchers start a technical examination,

This next item is about forgery detection. A March 5, 2014 news release on EurekAlert describes the latest developments,

Gallery owners, private collectors, conservators, museums and art dealers face many problems in protecting and evaluating their collections such as determining origin, authenticity and discovery of forgery, as well as conservation issues. Today these problems are more accurately addressed through the application of modern, non-destructive, “hi-tech” techniques.

Getting back to this new technique, a May 28, 2014 Science and Technology Facilities Council news release, which originated the news item, provides information about the various agencies involved with this work and offers some technical detail about the new technique,

The new approach is derived from a technique called Spatially Offset Raman Spectroscopy (SORS). It was originally developed by UK researchers at the Science and Technology Research Council’s (STFC) Central Laser Facility within the Research Complex at Harwell. Now they have joined forces with researchers from the Institute for the Conservation and Promotion of Cultural Heritage (ICVBC), part of Italy’s National Research Council (CNR) to adapt this technology to test paintings without having to destroy any part of them.

The SORS technique involves shining the laser light onto an opaque object. A small number of photons (light ‘particles’) will scatter back, changing colour according to the different paint components they represent, and allowing the scientists to analyse the chemical composition in depth.

Professor Pavel Matousek, from STFC’s Central Laser Facility, explained. “Building on our earlier SORS research, we’ve transformed the method to allow us to probe the painted layers for the first time,” he said. “We’ve called it Micro-SORS because we can analyse the layers at the micrometer scale, rather than the usual millimetre scale”.

For comparison of scale, a human hair is about 100 micrometers wide.

Dr Claudia Conti, a scientist at the ICVBC in Italy, said, “When I heard about the potential of SORS and how it could be applied, I realised the huge contribution this method of analysis could bring to the conservation of artworks.”

The research team tested the Micro-SORS method by collecting data from the light scattered across a surface of painted layers, artificially prepared to mimic a real painting. They isolated the light signals of the individual paint layers, enabling them to assess the chemical make-up of each layer.

The next step in the team’s research is to optimise the sensitivity and depth of penetration, and apply the technique to real artwork.

SORS has been used in other applications, from the news release,

The original SORS technique has already been applied to a number of problems, including non-invasive breast cancer diagnosis and bone disease diagnosis.The Science and Technology Facilities Council (STFC) has also launched a spin-out company, Cobalt Light Systems, which uses the SORS technology and has recently developed products for scanning liquids in unopened bottles for airport security, and in pharmaceutical quality control.

Here’s a link to and a citation for the research paper,

Subsurface Raman Analysis of Thin Painted Layers by Claudia Conti, Chiara Colombo, Marco Realini, Giuseppe Zerbi, and Pavel Matousek. Applied Spectroscopy, Volume 68, Number 6, June 2014, pp. 686-691(6) doi.org/10.1366/13-07376 Available online via Ingentaconnect

This article is open access.