WildLens Chronicles

Greater Mouse-Eared Bats Can Use Polarized Twilight to Calibrate Their Compass

Echolocation is excellent at telling a bat what is nearby.
It does not solve long-distance navigation.
Greater mouse-eared bats use additional information.
In an experiment, female bats were allowed to view the twilight sky through filters that either preserved the natural direction of polarized light or rotated that pattern by 90 degrees.
Later, the bats were released elsewhere at night.
Animals exposed to the shifted polarization pattern changed their departure orientation relative to bats that had seen the natural pattern.
The researchers concluded that these bats can use polarization cues at sunset to calibrate a magnetic compass used afterward.
That does not mean polarization is a universal navigation system in every bat. Experiments on other bat species have produced different results.
The interesting point is narrower:
a nocturnal mammal can obtain useful directional information from the structure of daylight just before darkness arrives.
The bat does not need to see the sun itself.
Information remains written across the sky after sunset. Nature

Eorhynchochelys Had a Toothless Turtle Beak but No Complete Turtle Shell

Turtle anatomy did not evolve in one package.

Eorhynchochelys sinensis makes that especially clear.

This Triassic reptile had a toothless beak resembling one of the defining features of later turtles.

But the body lacked a fully developed shell.

Its ribs were broad and flattened, pointing toward the structural changes that would later become integrated into the carapace, yet the familiar upper shell had not formed.

That creates a different sequence from Odontochelys, which lived later and had a complete plastron beneath the body but an incomplete dorsal shell.

Together, these fossils show that recognizable turtle traits appeared in different combinations through time.

Beak.

Broadened ribs.

Ventral shell.

Dorsal shell.

The final turtle body plan was assembled from components rather than appearing all at once.

Eorhynchochelys is especially useful because one feature that looks unmistakably “turtle” — the beak — evolved while much of the rest of the animal still did not.

A Pregnant Seahorse’s Brood Pouch Becomes More Vascular as Embryos Develop

Male seahorse pregnancy is more than carrying eggs in a pocket.

The brood pouch changes through gestation.

Studies of pot-bellied seahorses found that the inner pouch surface becomes increasingly folded while the vascular network expands.

Capillaries grow denser and move closer to the pouch cavity.

Those changes reduce the distance across which respiratory gases must diffuse between father and developing embryos.

Other work shows the pouch also regulates ions, waste and aspects of nutrition.

Recent cellular studies describe specialized pregnancy tissues with placenta-like functions, although the structure evolved independently from the mammalian placenta.

That distinction matters.

A seahorse male is not using a mammalian female reproductive organ in reverse.

Evolution built a gestational system from different tissue and a different anatomical starting point.

Yet pregnancy creates similar physical problems in both cases:

exchange oxygen,

manage waste,

control the internal environment,

support developing young.

Different bodies can arrive at surprisingly similar functional solutions.

Yi and Ambopteryx Tried a Wing Design That Did Not Lead to Bird Flight

Not every dinosaur that entered the air used feathered wings.

Yi qi and Ambopteryx belonged to a small lineage of scansoriopterygid dinosaurs with a radically different structure.

An elongated wrist bone supported a membrane extending between the body and forelimb.

The arrangement has been compared superficially with bat or flying-squirrel membranes, but its exact geometry was unique.

Aerodynamic modeling and laser-stimulated-fluorescence work indicate these dinosaurs were probably arboreal.

Powered flight was highly unlikely.

Their gliding performance also appears to have been limited compared with many living gliders and feather-winged contemporaries.

That makes the lineage especially valuable.

Evolution was not following one inevitable route toward an airborne dinosaur.

Different body plans were being tested.

One lineage eventually produced the highly successful feathered flight system inherited by birds.

The membrane-winged experiment disappeared without known descendants.

A structure can work well enough to evolve — without becoming the design that survives.

New Research Points to DNA Repair as Part of the Bowhead Whale’s Extreme Longevity

Bowhead whales can live for more than two centuries.

That creates a biological problem.

A long-lived, very large animal has many cells and many years in which DNA damage can accumulate.

Yet bowheads are not known for exceptionally high cancer rates.

A 2025 study compared bowhead whale cells with cells from other mammals.

Bowhead fibroblasts showed more efficient and more accurate repair of double-strand DNA breaks, along with lower mutation rates.

Researchers identified one protein, CIRBP, as especially abundant in bowhead tissues.

Increasing CIRBP levels improved DNA-repair performance in experimental systems, and expressing it in fruit flies increased resistance to radiation and extended lifespan.

That does not mean one protein explains a 200-year life.

Nor does it establish a ready-made human longevity treatment.

The result identifies one cellular strategy that may contribute to the whale’s unusual combination of large body, long life and genome stability.

Some animals respond to damaged cells by eliminating them aggressively.

Bowheads appear unusually good at repairing the damage accurately.

Oculudentavis Became a Case Study in How Fossil Identification Can Change

The first Oculudentavis skull looked extraordinary.

It was tiny.

It was trapped in Cretaceous amber.

And in 2020 it was described as a hummingbird-sized bird-like dinosaur.

The interpretation did not last.

Anatomical objections appeared quickly, especially around features that looked more lizard-like than avian.

A second specimen preserved more of the body.

Later work placed Oculudentavis among squamates — the reptile group containing lizards and snakes — rather than among birds or dinosaurs.

Broader analyses of early squamate anatomy have since provided additional support for that placement.

The original bird interpretation was retracted.

That does not make the fossil less interesting.

Its strange skull remains highly unusual even among lizards, and amber preserved anatomy that would rarely survive in ordinary sediment.

The story is valuable precisely because paleontology corrected itself.

A spectacular interpretation was published.

More evidence appeared.

The animal changed branches on the evolutionary tree.

A Dragonfly’s Hunting Flight Is Predictive, Not Just Reactive

A dragonfly does not simply chase the insect directly in front of it.

High-speed motion tracking shows a more sophisticated interception strategy.

During an attack, the dragonfly stabilizes the prey in a specialized region of its visual field while rotating its own body toward a future interception path.

Head movements compensate for expected changes produced by the dragonfly’s own steering.

Most of the maneuver can therefore unfold without waiting for each new visual error before correcting course.

Researchers described the control system using internal predictive models of both the predator’s movement and the prey’s trajectory.

Vision still matters continuously.

Unexpected prey movement triggers corrective responses.

But much of the ordinary steering is anticipatory.

Even before takeoff, perched dragonflies use visual criteria to decide whether a target is catchable and time departure around where the prey is expected to move.

The insect does not need to understand geometry consciously.

Its nervous system still solves a geometric problem:

do not fly toward where the prey is.

Fly toward where interception becomes possible.

The Eyes and Inner Ear of Shuvuuia Point Toward a Strongly Nocturnal Sensory System

A small dinosaur from the Gobi Desert preserved an unusual sensory combination.

Researchers compared eye anatomy and inner-ear structures across living birds and extinct theropods.

Shuvuuia deserti stood out.

Its eye proportions were consistent with strong low-light vision.

Its inner ear contained an unusually elongated auditory region, which the 2021 study interpreted as evidence of very sensitive hearing.

Together, the features were used to reconstruct Shuvuuia as a nocturnal predator.

The comparison with modern barn owls became especially memorable.

That specific hearing analogy now deserves caution.

A 2025 reanalysis argued that cochlear length alone cannot support some of the stronger claims previously made about dinosaur hearing performance.

So the evidence is not “Shuvuuia heard exactly like an owl.”

The safer conclusion is that its sensory anatomy was unusually specialized and strongly supports nocturnal ecology, while the exact quality of its hearing remains harder to reconstruct.

A fossil ear can narrow the possibilities without reproducing the soundscape itself.