Previously, in 1906, explorer Lorobek discovered only one other turtle, a large male turtle, there. Scientists believed that this animal was the last of the “fantastic giant tortoises” or Chelonoidis phantasticus and extinct the species.
Then they found Fernanda.
However, when Fernanda was first compared to the 1906 male specimens stored in the California Academy of Sciences collection, the two looked so different that scientists asked if they were of the same species. Had to question.
Inside the Galapagos Giant Tortoise, there is a dome-shaped upper shell called the shell, which resembles an upside-down bowl. However, some species, such as Fernandina’s male specimens, have a saddleback-style shell with the front of the upper shell above the head and neck arched upwards, Jensen said. increase.
“The shell arch greatly expands the range of motion of these turtles’ necks, allowing them to reach higher positions to eat plants off the ground, so they have more food in their hands. It may have evolved to get in, “Jensen said.
The 1906 turtle was in the shape of an extreme saddleback with a distinctive flare around the edges. Therefore, it was called “Fantastics”.
The native status of the Fernandina tortoise was questionable. Because some wondered if her growth was hindered and the features were distorted, but she had this flared-free, small, smooth shell.
Fernandina turtles were thought to be extinct due to the island’s active volcano, which erupted about 25 times in the last two centuries. Lava flows may have reduced the small pockets of plants that turtles can live and feed. The island is isolated along the western edge of the archipelago.
Read between genetic lineages
To answer the question of Fernanda’s heritage, the research team first sequenced the complete genome of Fernanda, then with the 1906 turtle genome, and the genomes of the other 13 species of giant tortoises in Galapagos. I compared. Fernanda’s DNA tells an amazing story, like the discovery of the turtle himself.
“To be honest, to my surprise, Fernanda was very similar to what I found on the island over 100 years ago, and both were very different from the turtles on other islands,” co-authored. Stephen Golan, a geneticist and postdoctoral fellow at Princeton University, said in a statement.
The species, which was thought to be extinct for 100 years, finally had a proven living member.
Adargisa Cacone, a senior research scientist and senior research author at Yale University, suggests that Fernanda may be a hybrid created by illusions that cross with extinct species that inhabit the adjacent large island of Floreana. Did. But more information is needed. Specifically, finding more turtles in Fernandina.
There is evidence to suggest that there may be something more fantastic. The turtle scat was discovered on the island in 2014. Much of Fernandina has not yet been explored, as vast lava fields prevent anyone from reaching its interior.
“Fernandina Island is the tallest, geologically young, giant mountain of jagged chunks of predominantly brown lava,” said Professor Emeritus of Zoology at Princeton University, Ecology and Evolutionary Biology. Peter Grant, an emeritus professor of scholarship, said. statement. “At lower altitudes, vegetation occurs in recently solidified lava sea island-like masses. Fernanda was found in one of these, evidence that a few relatives may be present in the other. there is.”
Two expeditions looking for more turtles, such as Fernanda, have failed since their discovery in 2019, but Galapagos National Park and Galapagos Reserve carry out more campaigns in hopes of protecting the species. intend to do something.
Fernanda currently lives in the Faustrerena Giant Tortoise Breeding Center in the park, which functions as a rescue and breeding facility. If more turtles such as Fernanda are found, conservationists can initiate a captive breeding program to keep her seeds alive. Both Fernanda and the 1906 turtle have a very high genetic diversity compared to other species of Galapagos elephants, Jensen said.
“This means that even if several other Fernandina turtles are found and bred together, all offspring are unlikely to be adversely affected by inbreeding,” she said.
Live at the last minute
Galapagos giant tortoises can’t swim, but how did they get to the island in the first place? It turns out that they can float. That is, hurricanes and storms can carry them.
About two or three million years ago, a storm carried giant tortoises from South America to the west. Turtles bred on the landed islands and evolved rapidly. This mating gave birth to 14 species, all of which were descendants of one ancestor.
The biggest difference between these turtles is the shape of the shell. Domed turtles live in high-altitude, humid environments, and saddleback turtles live in lower, dry ecosystems.
Studies show that the number of Galapagos giant tortoises has fallen by 85% to 90% since the early 1800s when whalers and pirates first arrived in the archipelago. When pirates raided South American colonies and whalers hunted in the surrounding waters, they fed on giant tortoises.
Turtles could live for months without food or water, so sailors filled the hull of the ship with live turtles and slaughtered them for fresh meat along the way.
And when it was time to lighten the luggage, the living turtles were thrown into the sea. Some floated and landed on another island.
“For this reason, some islands have turtles that are descendants of these abandoned turtles and have a genetic identity that does not match the local species, but in many cases the abandoned turtles are local species. “I crossed with Jensen.”
All 14 species are on the International Union for Conservation of Nature’s Red List, ranging from vulnerable to extinct.
Turtles, the largest cold-blooded terrestrial herbivore found on Earth, play an important role as a stabilizing agent in the Galapagos Islands.
“The presence of turtles maintains certain types of ecosystems and vegetation communities that are natural to the island,” Jensen said. “When a turtle is removed from the photo, the environment changes, which affects all other species that depend on the ecosystem that the turtle maintains.”
Fernanda is estimated to be over 50 years old and is a true survivor. In the face of lava flows, she prolongs volcanic eruptions and habitat shrinkage. And whether she is the last of her kind or just the beginning, Fernanda gives researchers the hope that invisible species can still survive.
Source: www.cnn.com
