◎ Science and Technology Daily reporter Zhao Hanbin
Recently, a number of research groups at the Kunming Institute of Zoology of the Chinese Academy of Sciences have collaborated to confirm the echolocation ability of species of the rodent pigtail rat genus by integrating multiple independent evidences of behavioral, anatomy, genomics, and gene function experiments. "Science" magazine published a research article entitled "Echo Localization of Pigtail Rats" online on the 18th.
Echo localization refers to a directional behavior of animals that carry out activities such as navigation and foraging by comparing the differences in the information of sound waves emitted and receiving echoes. Well-known echolocation animals mainly include insectivore bats and toothed whales.
Chinese pigtail rat
Shi Peng's research group and Liu Zhen's research group of the State Key Laboratory of Genetic Resources and Evolution at the Kunming Institute of Zoology, Chinese Academy of Sciences have long been engaged in research on the convergence evolution and molecular genetic mechanism of echolocation, and have published a series of research papers in a number of top international journals; the veterinary ecology and evolution research group led by researcher Jiang Xuelong has long been engaged in the research of the behavioral ecology and phylogenetic development and classification of pigtail rats, and reported a new species of pigtail rat genus in 2017.
The researchers recorded that pigtail rats regularly emit short-range, FM, high-frequency sound waves during their movements. In dark environments, pigtail rats emit higher ultrasound rates in complex spatial environments and when avoiding obstacles. The above results suggest that the pigtail mouse ultrasound plays an echolocation role in the movement behavior. Subsequently, they used a classic experimental device and a rigorous experimental design to verify whether the pigtail rat had echo localization capabilities.
Multiple experimental evidence confirms that pigtail mice have the ability to echolocate.
Through behavioral task experiments, it was found that pigtail rats spend more time and emit higher ultrasonic speeds to explore targets, and they accurately detect the escape platform in complete darkness conditions and successfully obtain food rewards; when their ears are blocked, pigtail mice cannot receive echoes and can no longer detect targets and complete tasks; after removing earplugs, pigtail rats recover the ability to explore and locate targets. Under the conditions of eliminating vision, touch, and controlled smell, behavioral experiments have confirmed that the genus is targeted by emitting ultrasound waves and auditory reception echoes.
The three research groups worked closely together to comprehensively use behavioral experiments, anatomical feature analysis, comparative genomic analysis, gene function experiments and other cross-cutting research methods to confirm that the pigtail rat is a new mammal group that independently evolved echolocation adaptive traits, suggesting that people may have greatly underestimated the biodiversity of adaptive complex phenotypes.
The discovery of this new class of echolocated mammals has increased the number of independent origins and evolutions of adaptive complex trait echolocation to at least 6 times, becoming a typical case of trait convergence evolution in nature.
Source: Science and Technology Daily The pictures in the article are produced and provided by Liu Qi and Ma Xiaofeng of Kunming Institute of Zoology
Source: Science and Technology Daily