Surprisingly Revealed: According to one study, fossilized inner ears can reveal secrets about the abilities and behavior of extinct animals. Because it includes the organ of balance in addition to the auditory system, inner ear features allow conclusions about flight abilities and even brood care in early representatives of reptiles, dinosaurs or birds, paleontologists report. Behavior.
Armed with a shovel, brush, and measuring tape, paleontologists have long been concerned with the more superficial features of fossils: they described the shape, size, and physical features such as wings or feathers, which gave fundamental conclusions about the way of life. Removed. Of extinct animals. However, these fossil extracts were often unable to explain how they once moved and behaved. Opportunities for well-established insights into these questions are therefore very popular in paleontology. In this context, researchers led by Bharti-Anjan Bhullar from Yale University in New Haven are now focusing exclusively on the inner ear as a source of information.
“Equipment” with two functions
The small structure sits in the vertebral skull and incorporates two systems of perception: the inner ear is the cochlea and the organ of balance (vestibular organ). “Of all the structures that can be recreated from a fossil, the inner ear is probably the closest to a technological device,” says Bhullar. The characteristics of the cochlea are linked to the auditory ability of a living creature, and the properties of the organ of balance are similar to the way scientists move it. “If you are able to recreate its shape, you can draw conclusions about some of the characteristics and behaviors of extinct animals in an almost unprecedented way,” the paleontologist says.
Paleontologists have used the characteristics of the inner ear as an earlier clue – but Bhullar and his colleagues have now systematically shown the potential for this process. The technologies that are currently revolutionizing paleontology form the basis: micro- and nano-computed tomography makes it possible to see inside fossils and show hidden fine structures in detail. In this way, the inner ears in the fossil skull can now be examined in detail.
As part of their study, scientists have now analyzed, analyzed and categorized inner ear data of many current and extinct animal species. In today’s species, characteristics can be associated with the known behavior and abilities of the respective species. Characteristic signatures emerged in structures that can be compared to the fossilized inner ears of extinct species.
Feature similarities
As the researchers report, their data analysis led to groups of species with characteristics of the inner ear. The members of a cluster show a clear resemblance to how they move through the world and see it. The three groups are characterized by some structural features of the so-called vestibular system of the limb of equilibrium. “This three-dimensional structure provides information about the dynamics of an animal. The shape of the vestibular system thus represents a window for understanding bodies in motion, ”says paleontologists.
The vestibular cluster includes animals that walk on four legs. Other distinguishing features of the balance limb are typical for two-legged species, as well as less agile flight. These include, for example, modern chickens and gliders such as some seabirds and vultures. The third group then constructs clear aerial artifacts, such as today’s birds of prey and songbirds of many species. In terms of the characteristics of the inner ear of many primary wing carriers, data evaluations now make it clear: Pterosaurs or the famous “primal bird” Archeopteryx belonged to the category of less agile fliers, paleontologists report.
Notes on Brood Care Practices
As for the characteristics of the cochlea, the researchers were able to identify in the representatives of the archaea a characteristic feature, which is associated with hearing certain frequencies. Archaeosus not only includes extinct animal groups such as dinosaurs and pterosaurs – they also include today’s crocodiles and birds. As researchers point out, a distinctive feature of these animals is that they make sounds. Even in crocodiles, youngsters communicate with the mother, for example through sounds.
Results from paleontologists now indicate that the change of cochlear size in the archers’ ancestors was related to the development of high-pitched reproductive calls in young animals. “We discovered a transitional form of cochlea in Eupacaria”. These were the primary forms of archers from the Lower and Middle Triassic. “This suggests that the ancestors of Archaeosaurs started making sounds as they evolved into smaller predators,” the vet said.
As a research study, Yale University writes: “It is becoming clear that future inner ear studies will provide information on how an animal can move on land, in the air, or in water. In some cases, comparisons may also shed light on whether a species had grown bored of hearing the high voices of their children ”.
Source: Yale University, Article: Science, doi: 10.120 / science
