AUG 09, 2019 09:03 AM PDT

DNA Analysis Shows How Algae Respond to a Changing Environment

WRITTEN BY: Carmen Leitch

Researchers took a close look at what seem to be strands of pink bubblegum smeared on rocks off of the British Columbian coast - coralline algae - and discovered a cornucopia of species. The researchers wanted to know more about how ecosystems are changing and losing diversity. Often, the loss of apex predators can have terrible consequences for a biological community (known as trophic downgrading). Coralline algae appear to be one of the few species that has been able to tolerate the loss of the apex predator in its community, while many of its neighbors aren't faring so well. There is more to the story, however, which has been reported in the Proceedings of the National Academy of Sciences (PNAS) and is outlined in the video.

"Corallines play really important roles in their ecosystem, from cementing coral reefs together to giving off scents that attract other species like sea urchins, abalone, corals, and kelps to the area," said Patrick T. Martone, a professor of botany at University of British Columbia (UBC) who oversaw the research. "Some coralline species are better at attracting organisms than others and respond to climate stressors like rising ocean temperatures in different ways. But they all look the same so it's hard to tell how changes to their environment are really impacting them."

The researchers used DNA analysis to learn more about the numerous species of coralline algae. This diversity might be the key to preserving marine habitats such as kelp forests. When sea otters, an apex predator or keystone species, disappear from the area, sea urchins thrive, and their growth destroys kelp forests. The result is a so-called sea urchin barren, where few species can live, except for coralline algae.

"The fact that corallines do better in this environment would be an exception to our understanding of the impacts of losing keystone species like sea otters, which typically result in an overall loss of biodiversity," said Martone.

The scientists compared the DNA they harvested from coralline algae growing in kelp forests to that growing in sea urchin barrens to see how the algae may be impacted by the change in habitat. The algae sampled from kelp forests were similar to each other but different from what was growing in the barren areas; there had been a reduction in species diversity.

Coralline algae in a kelp forest. Credit: Jenn Burt

"What we found is that there are a lot of species down there," said the lead study author Katharine Hind, Ph.D. "And while some corallines do grow more abundantly in sea urchin barrens, we found more species and greater diversity in kelp forests."

"So what we begin to see is actually a loss of coralline diversity, despite the apparent increase in abundance. This greater understanding changes our interpretation of the ecological pattern - a lesson that should be applied to cryptic species in other biological systems, like fungi, insects, or plants on land," said Hind. "It's possible we could be losing some kind of ecosystem function as a result of this loss of diversity."

Now the scientists want to know more about the various species of corallines they found and what they do.

Coralline algae in a sea urchin barren. / Credit: Jenn Burt

"We are seeing a decline in kelp forests along the coast as they are being replaced by these urchin-dominated barrens," said Martone. "We think corallines might hold the key to understanding the maintenance of urchin barrens; certain species that urchins prefer to settle on could result in a positive feedback to bring more urchins to the area. Conversely, corallines that kelp spores respond more positively to could help bring kelp forests back to stripped reefs."


Sources: AAAS/Eurekalert! via UBC, PNAS

About the Author
  • Experienced research scientist and technical expert with authorships on 28 peer-reviewed publications, traveler to over 60 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
AUG 19, 2019
Genetics & Genomics
AUG 19, 2019
Are Our Instincts Really Genetic?
Genetic explanations for our instincts are incomplete. Although they explain to some degree how we learn and suggest how these learnings are passed on, the...
AUG 19, 2019
Cancer
AUG 19, 2019
Skin Color Protein Used to Better Evaluate Skin Cancer
The large, complex molecules known as proteins perform many crucial functions in the human body. By carrying out diverse kinds of work in our cells, they k...
AUG 19, 2019
Genetics & Genomics
AUG 19, 2019
Does Viral DNA in the Human Genome Cause Disease?
Millions of years ago, retroviruses interacted with our primordial ancestors, and it's estimated that 8% of the human genome comes from viruses....
AUG 19, 2019
Microbiology
AUG 19, 2019
To Survive Environmental Challenges, Red Algae Grab Bacterial Genes
Cyanidiales are a group of red algae species. Researchers have found that about 10% of them have acquired genes from bacteria....
AUG 19, 2019
Cell & Molecular Biology
AUG 19, 2019
New study finds that the structure of chromosomes may not be as important to transcriptional activity as we once thought
New study finds the chromatin structures (heterochromatin and euchromatin) may not be determinate of whether genes in a particular region of a chromosome get expressed....
AUG 19, 2019
Genetics & Genomics
AUG 19, 2019
Revealing the Epigenetic Patterns That Specific Enzymes Create
Genomic DNA is modified by chemical markers called epigenetic tags, which can change gene expression without altering the underlying genetic code....
Loading Comments...