Due to climate change, one-third of animal parasites may be extinct by 2070

September 6, 2017, Smithsonian
An assortment of specimens from the Smithsonian's National Parasite Collection at the National Museum of Natural History. Credit: Adrian Van Allen

The Earth's changing climate could cause the extinction of up to a third of its parasite species by 2070, according to a global analysis reported Sept. 6 in the journal Science Advances. Parasite loss could dramatically disrupt ecosystems, and the new study suggests that they are one of the most threatened groups of life on Earth.

Parasites have an admittedly bad reputation. The diverse group of organisms includes tapeworms, roundworms, ticks, lice, fleas and other pests—most of which are best known for causing disease in humans, livestock and other animals. But parasites play important roles in ecosystems. They help control wildlife populations and keep energy flowing through food chains.

Because many parasites have complex life cycles that involve passing through different host , parasite diversity can be considered a sign of a healthy ecosystem, says Anna J. Phillips, a research zoologist and curator of the U.S. National Parasite Collection at the Smithsonian Institution's National Museum of Natural History. "Having parasites is a good indicator that the ecosystem has been stable," she says. "It means the system has a diversity of animals in it and that conditions have been consistent long enough for these complex associations to develop."

Despite their critical contributions to ecosystems, parasites have drawn less attention from conservation biologists than more charismatic creatures. Until now, they have largely been left out of studies of climate change and its impacts, says the study's lead author Colin Carlson, a graduate student in Wayne Getz's laboratory at the University of California, Berkeley.

Anna J. Phillips, research zoologist and curator of the National Parasite Collection at the Smithsonian's National Museum of Natural History, with Taenia saginata, the beef tapeworm. Credit: Paul Fetters for the Smithsonian Institution

To find out how climate change is likely to affect the survival of a wide range of , Carlson and colleagues turned to museum collections. The U.S. National Parasite Collection, an expansive set of worms, fleas, lice and other parasites, provides a broad and deep record of different species' occurrences around the world. The still-growing collection began in 1892 and now contains millions of organisms. Most species are represented by many specimens, meaning researchers can use the museum's records to investigate organisms' geographical distributions and predict changes over time.

Records from the U.S. National Parasite Collection were combined with additional information from specialized databases cataloging ticks, fleas, feather mites and bee mites to enable a comprehensive global analysis.

Before they could begin their analysis, the research team needed to know exactly where each specimen came from so they could understand each species' habitat needs. In recent years it has become standard to pinpoint a specimen's original location with GPS coordinates in collection records, but the locations associated with older specimens tend to be less precise. So the team, which included 17 researchers in eight countries, spent years tracking down the exact geographical source of tens of thousands of parasite specimens, adding GPS coordinates to their database wherever possible. That information was essential for the current study and will also aid in future research.

Once the geospatial information was complete, the data could be used to make predictions about how parasites will fare as the Earth's climate changes. Using climate forecasts, the researchers compared how 457 parasite species will be impacted by changes in climate under various scenarios.

An assortment of specimens from the Smithsonian's National Parasite Collection at the National Museum of Natural History. The National Parasite Collection holds more than 20 million parasite specimens in connection with information about their geographic distribution and host animals. A team of researchers drew on this collection to analyze the impact of climate change on parasite biodiversity in the 21st century. Credit: Paul Fetters for the Smithsonian Institution

The analysis determined that parasites are even more threatened than the animal hosts they rely on. The most catastrophic model predicted that more than a third of parasite species worldwide could be lost by 2070. The most optimistic models predicted a loss of about 10 percent. "[Slowing ] has a really profound impact on extinction rates, but even in the best-case scenario, we're still looking at fairly major global changes," Carlson says.

Parasites need to be included in conversations about conservation, and this study highlights their delicate position in complex ecosystems, the scientists say. "Parasites are definitely going to face major extinction risk in the next 50 years," Carlson says. "They are certainly as threatened as any other animal group." To share what they've learned, the team created an online parasite "Red List" that identifies the extinction threat level of each species in their study.

Much of conservation biology focuses on single species, but it is important to keep in mind the goal of conserving ecosystems as a whole. "As long as there are free-living organisms, there will be . But, the picture of parasite biodiversity in 2070 or beyond has the potential to look very different than it does today based on the results of these models," Phillips says.

Explore further: Climate change could kill off parasites, destabilizing ecosystems

More information: C.J. Carlson el al., "Parasite biodiversity faces extinction and redistribution in a changing climate," Science Advances (2017). advances.sciencemag.org/content/3/9/e1602422

Related Stories

Parasites of endangered animals should be conserved

March 21, 2016

Conservation managers who try to keep members of endangered animal species parasite-free are well-intentioned but this approach is misguided, according to a new research paper co-authored by a zoologist at New Zealand's University ...

Recommended for you

Floodplain forests under threat

March 19, 2019

A team from the Institute of Forest Sciences at the University of Freiburg shows that the extraction of ground water for industry and households is increasingly damaging floodplain forests in Europe given the increasing intensity ...

Scientists discover common blueprint for protein antibiotics

March 19, 2019

A discovery by researchers at the Los Angeles Biomedical Research Institute (LA BioMed) has uncovered a common blueprint for proteins that have antimicrobial properties. This finding opens the door to design and development ...

Nanoscale Lamb wave-driven motors in nonliquid environments

March 19, 2019

Light driven movement is challenging in nonliquid environments as micro-sized objects can experience strong dry adhesion to contact surfaces and resist movement. In a recent study, Jinsheng Lu and co-workers at the College ...


Adjust slider to filter visible comments by rank

Display comments: newest first

1 / 5 (8) Sep 06, 2017
Paper is at: http://advances.s...422.full

Phys.Org -- "The most catastrophic model predicted that more than a third of parasite species worldwide could be lost by 2070." Of course

1st words of Abstract read "Climate change is a well-documented driver of both wildlife extinction and disease emergence…" Are we talking about dinosaurs, mastodons, dodo birds? Where is one documented or even suspected case of extinction due to climate change it the past 300 years?

Referenced work: Extinction risk from climate change paper states "Climate change over the past approximately 30 years has produced numerous shifts in the distributions and abundances of species and has been implicated in one species-level extinction."
1 / 5 (8) Sep 06, 2017

Foundation materials contradict the paper and contain wide ranges of numerical over wide range of time periods. Also some of work seems old circa 2004 which is further built on older work. It would seem that with the deluge of all "CC might" research more current supporting material could be used in places.

"The data sets included in this study represent some of the only true "big data" for wildlife parasites; a number of the largest data sets do not include any spatially explicit data,". There exists "big data" for parasites? Yes but that only applies to the life blood being sucked out of society by welfare state Fed, State, and Local governments.
1 / 5 (7) Sep 06, 2017

It would be nice to see a good separation of extinction due to CC vs. other anthropogenic impacts like slaughter, introduced disease invasive, species displacement, habitat destruction, etc.

In summary this is built on wide ranging estimates of wide ranging estimates. With fuzz built upon so much fuzz maybe it all combines together to

Conclusion: Taxpayers may not have been ripped off. This is academic exercise apparently funded with little or no Federal funding.

No worry be happy without hosts they will be unnecessary for the ecosystem. Nature abhors a void. Other parasites always fill in.
4.8 / 5 (6) Sep 06, 2017
Turgent, you display a great facility for fecal regurgitation. While that in itself might be considered admirable by some, non-delusional people simply smell your filthy stench. I, for one, will no longer witness your puking of sheeyit. You are now ignored.
1 / 5 (5) Sep 06, 2017
Since the climate has been changing for 4.545 billion years, that's a lot of dead parasites, I tell you what.

Have you hugged a fracker today? You should.
Sep 06, 2017
This comment has been removed by a moderator.
Sep 06, 2017
This comment has been removed by a moderator.
3.3 / 5 (7) Sep 07, 2017
Where is one documented or even suspected case of extinction due to climate change it the past 300 years?

Many species have gone extinct in the last 300 years, but to prove it was due to climate change is of course very difficult. If a species, in a seemingly undisturbed area goes, extinct, how do you find out exactly what caused it?
It won't be climate directly, but a combination of factors such as disease, predators, parasites, food, availability breeding sites etc etc. Any or all of which can/is/are influenced by climate.

But give the golden toad (Incilius periglenes) a look. It was discovered in '66 and extinct in '89.
You can bet if there is one we know about, there are many we don't. Any number of invertebrates in the same habitat as the toad might also have gone extinct and we would never know about it.
Every species also carries within itself a partially unique micro-flora and parasite community, multiplying the numbers.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.