Arachnophobia warning and weak hearts: These are things of nightmares, so you might need to continue with caution.
The biological team at the University of Michigan documented 15 rare and disturbing interaction of predator-prey in the Amazon rainforest, including images stored at night on a tarantula-size plate for dinner that pulls the young opossum through the forest.
Photographs are part of a new journal titled "The ecological interactions between arthropods and small vertebrates in the lowland Amazon rainforest". Arthropods are invertebrates with segmented bodies and compounded additives that include insects, spiders (spiders, scorpions, mites and ticks) and crabs.
Article, scheduled for online publication on February 28th Protection of amphibians and reptiles, the details of cases of arthropodic predators – mainly large spiders along with several centipede and gigantic water bug – spin on vertebrates such as frogs and plumheads, lizards, snakes, and even small opossum.
"This is an underestimated source of mortality among vertebrates," said Daniel Raboski, an evolutionary biologist at the University of Michigan. "The surprising amount of deaths of small vertebrates in Amazon is probably due to arthropods such as large spiders and stones."
Once or twice a year, Raboski is led by a team of U-M researchers (faculty members, postdoctors, graduates and students) and international associates on a one-month expedition to the Los Amigos biological station in the remote Madre de Dios region of southeastern Peru.
The location of the study, in plain Amazon rainforests near the foot of Anda, lies at the heart of one of the most diverse ecosystems on the planet. The main research focus of the team is ecology of reptiles and amphibians. However, over the years, scientists testified and documented numerous interactions between predators of arthropods and liver vertebrates.
"We continued to record these events, and at one point we realized that we had enough observations to put them together in one work," said Raboski, associate professor at the Department of Ecology and Evolutionary Biology and curator associate at the UM Museum. Zoologists.
Spiders are among the most diverse arthropod predators in the tropics, and previous reports of the spinning of Amazon spiders include the prey of all major taxonomic groups of vertebrates: fish, amphibians, reptiles, birds and mammals.
But knowledge of these interactions remains limited, especially given the diversity of vertebrate prey and potential arthropods in tropical-rich species. The new work contains observations from 2008, 2012, 2016 and 2017.
"These events provide an overview of many links that form food networks, and provide an insight into an important source of mortality in the vertebrate that appears less common outside the tropics," says the first author of the study, Rudolf von Mai, a postdoctoral researcher in the Labos lab.
"Where we do this research, there are about 85 species of amphibians – mostly frogs and frogs – and about 90 species of reptiles," said Fon Mai. "Bearing in mind that there are hundreds of invertebrates potentially damaging vertebrates, the number of possible interactions between species is enormous, and this is highlighted in this paper," said von May.
In addition to the biological station in Los Amigos, other observations were made at the Villa Carmen biological station, also in the Peru region of Madre de Dios, and at the Madre Selva research station in the Loreto region of northern Peru.
Almost all visions were made at night, when they were the most active predators. During nighttime research, team members slowly pass through the noise with flashlights and headlights, in one file, scanning the forest and carefully listening.
During one of those nightly shots, Doctor's candidate U-M Michael Grundler and two other students "heard some scabs in the leaves."
"We looked at and saw a big tarantula at the top of the veil," said Grundler, co-author of the newspaper. "Possum was already caught by the tarantula and still fought badly at that moment, but after about 30 seconds he stopped hitting." Tarantula was the size of the plate, and the young mouse opossum was the size of the softball. Grundler's sister Maggie pulled out her mobile phone and took photos and videos.
Later, an expert on opium in the American Museum of Natural History confirmed that he had recorded the first documentation of a large migralomorphic spider who deals with opossum. The Migalomorphae infrared device is a group of mostly lush, stubborn spiders that include tarantula.
"We were pretty ecstatic and shocked, and we could not really believe what we saw," said Michael Grundler. "We knew that we were witnesses of something quite special, but we did not know it was the first observation after that."
Most of the pre-arterial arthropods rely on specialized parts of the body and poison to capture and paralyze the liver of the vertebrates. These adaptations include modified jaws, enlarged beaks and massive tusks. Some groups have developed dozens of protein poisons that are injected during capture.
Other interactions between predators and prey documented in Protection of amphibians and reptiles paper includes:
A few examples of large spiders from the Ctenidae family that catch on frogs and also a lizard. Most of the cases of extinction documented in the work include spiders, and most of them are ctenids, which are usually called wandering spiders. Ctenid spiders are predatory predators that catch at night and use special hair on their feet to detect vibrations of air and the direction of prey. Their main eyes are responsible for discrimination against objects, while secondary eyes reveal movement.
A large skolopendrid stonoga that consumed a lively Catesbi's snake-snail, and another stonem that ate the dead coral snake it had deflated. "Coral snakes are very dangerous and can kill people," said U-M doctoral candidate and co-author Joanna Larson. "It seemed surprising to see some sort of anthropologist take it off. In fact, these stonogeos are terrible animals."
In addition to predator events, researchers also report deadly infections of parasites in lowland amazon frogs and the commensal relationship between spider and frog. A commensal relationship is one in which one organism benefits, and the other is not damaged.
"One of the best things to do in Peru is the number of species that are daily encountered simply by walking in the forest," says Larson, who is studying the evolution of a child in frogs. "Every day you see something new and exciting."
"One part of the work we did was this collection of strange natural historical events we attended, including arthropodic predators and vertebrates," she said. "I still have not reached the level from which I was piled up. We'll see what else Peru can offer."
Other authors, besides Raboski, von Maia, Michael Grundler and Larson, are Emanuele Biggi from the International League of Conservation Photographers; Heidi Cardenas and Roi Santa-Cruz from Museo de Historia Natural de la Universidad Nacional de San Agustin, Peru; M. Isabel Diaz from the University of San Antonio de Abad del Cusco and the Museo de Biodiversidad del Peru, both in Peru; Consuelo Alarcon of John Carroll Universites and Museo de Biodiversidad del Peru; Valia Herrera, Mayor of Nacional San Marcos University, Peru; Francesco Tomasinelli from Milan, Italy; Erin P. Vesteen and Maggie R. Grundler at the University of California at Berkeley; Ciara M. Sanchez-Paredes from the University of Peruana Caietano Heredia, Peru; and Pascal O. Title and Alison R. Davis Raboski from the U-M Museum of Zoology and the Department of Ecology and Evolutionary Biology.
Field research was supported by the David and Lucile Packard Foundation Daniel Rabboski, as well as the Amazon Conservation Society, the Wildlife Conservation Society, Rosemary Grant Avard, the Edwin C. scholarship. Hinsdale UMMZ and the University of Michigan.