Nearly 200 kilometers from the sea, red mangroves thrive in the rainforests along the San Pedro Mártir River on the Yucatán Peninsula. But how did these tangled trees that typically grow in salty water along coasts end up trapped so far inland and in freshwater?
Carlos Burelo has been mulling a version of that question ever since he visited the river on a fishing trip with his father 35 years ago. As a kid, he saw how the mangroves with their twisted aboveground roots were different from other trees, an observation that stuck with him into adulthood as a biologist at the Universidad Juárez Autónoma de Tabasco in Villahermosa, Mexico.
Now, genetic analyses, surveys of vegetation and sediments and simulations of shifts in sea levels show that the red mangroves (Rhizophora mangle) are part of a “relict ecosystem” that has existed for more than 100,000 years. When warming during the last interglacial period, which peaked about 130,000 years ago, raised sea levels approximately 9 meters above present-day levels, the lowlands of what’s now the Yucatán Peninsula flooded.
Carlos Burelo has been mulling a version of that question ever since he visited the river on a fishing trip with his father 35 years ago. As a kid, he saw how the mangroves with their twisted aboveground roots were different from other trees, an observation that stuck with him into adulthood as a biologist at the Universidad Juárez Autónoma de Tabasco in Villahermosa, Mexico.
Now, genetic analyses, surveys of vegetation and sediments and simulations of shifts in sea levels show that the red mangroves (Rhizophora mangle) are part of a “relict ecosystem” that has existed for more than 100,000 years. When warming during the last interglacial period, which peaked about 130,000 years ago, raised sea levels approximately 9 meters above present-day levels, the lowlands of what’s now the Yucatán Peninsula flooded.
