Question

q es simbiosis de algae la relacion plis eb ingles

Answer 1

The oldest previous evidence of lichens, discovered in Scotland, dates back 400 million years. The finding also adds to the scant record of fossil fungi and raises new questions about the evolution of lichens.
The researchers are Xunlai Yuan (paleontologist at the Institute of Geology and Paleontology of Nanjing), Shuhai Xiao (associate professor of geosciences at Virginia Tech), and Thomas N. Taylor (professor of ecology and evolutionary biology at the University of Kansas)
Yuan, Xiao, and their collaborators have explored the Doushantuo Formation in southern China for a decade and have co-authored numerous reports of fossil discoveries, including algae and animal embryos.
Lichen is an association of two organisms that collaborate to survive in an inhospitable environment, such as rock exposed to the weather. One of the companions, a cyanobacterium or a photosynthetic algae, or both, can produce food from carbon dioxide, while the other partner, a fungus, provides moisture, nutrients, and protection for the association.
Current examples of such relationships at sea are abundant. Now, there is an example that goes back 600 million years ago.
In a place where abundant algae lived in a shallow environment about 600 million years ago, Yuan and Xiao found three specimens that show evidence of two companions in a family relationship. Clearly, there are two types of organisms living together and, researchers believe, interacting in a non-causal association.
In modern lichens and 400-million-year-old Scottish fossils, cocoidal cells provide nutrients, and fungal filaments provide protection against dehydration. But in the marine environment, dehydration is not a problem, and rocks 600 million years ago also contain many fossils of cocoidal cells that are not surrounded by fungal filaments. So it turns out to be an association in the form of lichen but quite flexible, because organisms are not obligated to live together.