Beneath the vibrant greens of the rainforest and the deep blues of the ocean, a splash of brilliant orange paints the rocks, trees, and sidewalks of Windward Oʻahu. This isn't rust or decay—it's a thriving, mysterious, and scientifically fascinating world of life waiting to be explored.
Welcome to the hidden realm of the Trentepohliales, an unusual group of terrestrial green algae that masquerade in shades of orange and red. For a student scientist in the University of Hawaiʻi's Marine Option Program (MOP), these algae became the subject of an intensive research project. This isn't just about naming species; it's a detective story about biodiversity, adaptation, and understanding the intricate web of life that thrives in our own backyards, from the moist cliffs of the Koʻolau Range to the bark of a familiar mango tree.
First, a paradox: why are these green algae so… not green? The answer lies in their clever survival strategy. While they contain chlorophyll (which is green), they produce high levels of orange and red pigments called carotenoids, primarily beta-carotene. These pigments act as a sunscreen, protecting the algae's delicate cellular machinery from the intense ultraviolet radiation they're exposed to on land.
The Trentepohliales play a quiet but crucial role in their ecosystems. They are:
Despite their importance, their diversity in tropical island ecosystems like Hawaiʻi is poorly understood. This knowledge gap was the driving force behind the MOP student's project.
The core mission was systematic: to find, identify, and catalog the species of Trentepohliales along the windward coast of Oʻahu.
Armed with GPS, camera, and sample bags, the student collected samples from diverse locations.
Samples were examined under microscopes to document physical features.
Genetic material was extracted and amplified using PCR techniques.
DNA sequences were compared to international databases for identification.
Samples were collected from various micro-habitats across Windward Oʻahu, each with distinct environmental conditions.
The results revealed a surprising diversity hidden in plain sight.
| Species (Genus) | Common Habitat Substrate | Description |
|---|---|---|
| Trentepohlia abietina | Tree bark (e.g., Mango, Guava) | Forms dense, fuzzy orange patches. Very common in humid areas. |
| Printzina lagenifera | Rock faces & concrete walls | Has distinctive barrel-shaped cells. Thrives in sun-exposed, rainy areas. |
| Trentepohlia aurea | Shaded rock overhangs | Exhibits a more golden-orange color. Prefers stable, moist environments. |
| Location Number | General Location | Substrate | Humidity | Sun Exposure |
|---|---|---|---|---|
| Site 1 | Manoa Falls Trail | Tree Bark | Very High | Low (Shaded) |
| Site 2 | Lanikai Pillboxes Trail | Basalt Rock | Moderate | Very High (Full Sun) |
| Site 3 | University Campus | Concrete Wall | Low | High |
| Site 4 | Lyon Arboretum | Various Trees | High | Variable |
| Sample ID | Morphological ID | Genetic ID (Top BLAST Match) | Similarity (%) |
|---|---|---|---|
| T-OAH-01 | Trentepohlia sp. | Trentepohlia abietina | 99.8% |
| T-OAH-07 | Printzina sp. | Printzina lagenifera | 100% |
| T-OAH-15 | Trentepohlia aurea | Trentepohlia aurea | 98.5% |
The genetic analysis was crucial. It confirmed that while two samples might look similar to the human eye, they could be genetically distinct species.
Distribution of identified Trentepohliales species across different habitat types on Windward Oʻahu.
What does it take to hunt for hidden algae? Here's a peek into the toolkit.
A chemical solution that breaks down tough algal cell walls to release DNA for analysis.
The "ingredients" that target and amplify a specific gene from the tiny extracted DNA sample.
A jelly-like matrix used to visualize and confirm that the DNA amplification was successful.
A simple press with blotting paper used to dry, preserve, and create permanent records of algal specimens.
Used to preserve tissue samples for long-term storage before DNA analysis.
Both stereo and compound microscopes are essential for morphological analysis of samples.
This student project is more than an academic exercise. It contributes a vital piece to the puzzle of Hawaiian biodiversity. By building a baseline catalog of what species exist and where they live, scientists can:
Tracking shifts in algal populations can serve as an early warning sign for changes in climate or air quality.
How did these algae get to Hawaiʻi? How have they evolved in isolation? This data helps answer those questions.
Trentepohliales are known for their high beta-carotene content, a valuable antioxidant. Understanding local species could open doors to novel natural products.
Each discovery adds to our understanding of tropical ecosystems and the incredible diversity of life on Earth.
The brilliant orange streaks on a hike are not just a splash of color; they are a testament to life's resilience and adaptability. Thanks to curious student scientists, we are one step closer to understanding the secrets of Oʻahu's smallest, and most colorful, forests.