Researchers have recorded the first real-time images of a tarantula's heart beating.
The video, captured with magnetic resonance imaging, or MRI, reveals how blood moves through the tarantula's heart, said study researcher Gavin Merrifield, a University of Edinburgh doctoral candidate.
"In the videos, you can see the blood flowing through the heart, and tantalizingly, it looks as though there might be 'double beating' occurring, a distinct type of contraction which has never been considered before," Merrifield said in a statement.
The MRI allowed researchers to measure the spider's heart rate and cardiac output (how much blood it pumps per beat) noninvasively as part of an ongoing study of tarantula biology.
"One potential practical use of this research is to ascertain the chemical composition of spider venom. Venom has applications in agriculture as a potential natural pesticide," Merrifield said.
"On the more academic side of things, if we can link MRI brain scans with a spider's behavior and combine this with similar data from vertebrates, we may clarify how intelligence evolved."
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