Month: July 2023

Nihohae

Nihohae matakoi was a dolphin that lived in the coastal waters around what is now Aotearoa New Zealand during the late Oligocene, about 25 million years ago. Part of a group known as waipatiids, it was much closer related to modern South Asian river dolphins than to modern oceanic dolphins.

Around 2m long (6’6″), it had unusually long tusk-like teeth at the front of its jaws, splaying out almost horizontally forwards and to the sides.

These teeth lay too flat to effectively interlock as a “fish trap”, and their fairly delicate structure and lack of wear marks suggests they also weren’t used for piercing large prey, sifting through gritty sediment, defending against predators, or for fighting each other. But Nihohae did have a highly flexible neck and the ability to quickly snap its jaws from side to side – although with a relatively weak bite force, suggesting it was primarily tackling small soft-bodied prey that could be easily swallowed whole.

Overall its feeding ecology seems to have been similar to modern sawfish, stunning prey such as squid with rapid slashing swipes of its jaws.

Funcusvermis

Biofluorescense is the term for when living organisms “glow” under certain types of light. Although it’s not usually directly visible to human eyes, wavelengths such as ultraviolet can reveal it – and we’re still only just starting to discover how widespread it really is in nature.

This phenomenon has been found in all major groups of modern amphibians, with most of them glowing green under UV, suggesting that it originated in their ancestors at least 300 million years ago.

So, ancient species like Funcusvermis gilmorei here could probably glow green, too!

Living during the late Triassic (~220 million years ago), fossils of Funcusvermis were found in what is now Arizona, USA. It’s only known from fragmentary remains, but those pieces are distinctive enough to identify it as the earliest known relative of modern caecilians.

It had a caecilian-like jaw with two rows of teeth, but unlike its worm-like modern relatives it still had small legs and wasn’t as highly specialized for burrowing. The shape of its vertebrae suggest it had a tubular body, and while its exact proportions and full length are unknown it may have been comparable in size to the smallest modern caecilians, around 10cm long (~4″).

Its combination of anatomical features gives further support to the idea that all modern amphibians share a common ancestor among the dissorophoid temnospondyls. The more distantly related but also caecilian-like Chinlestegophis may be a case of convergent evolution, representing a separate branch of temnospondyls that were coincidentally exploring a similar sort of lifestyle at around the same time.

São Miguel Scops Owl

When owls find their way onto isolated islands lacking any terrestrial predators, they have a tendency to take up that role for themselves – evolving longer legs and shorter wings, and specializing more towards hunting on foot. From New Zealand to Hawaii to the Caribbean to the Mediterranean to Macaronesia, leggy island ground-owls have independently happened over and over again in the last few million years—

—And, unfortunately, they’ve all also become victims of the Holocene extinction, their fragile island ecosystems too easily disrupted by human activity and the arrival of invasive species.

The São Miguel scops owl (Otus frutuosoi) was found only in the Azores on São Miguel Island. About 18cm tall (~7″), it was slightly smaller than its relative the Eurasian scops owl, with longer legs, a wider body, and much shorter wings.

Its wing proportions indicate it would have been a poor flyer, instead primarily hunting on foot in the dense laurisilva forests. Since there were no terrestrial mammals or reptiles on São Miguel at the time, its diet probably mainly consisted of insects and other invertebrates – and it would have in turn been the potential prey of larger predatory birds like buzzards and long-eared owls.

All currently known subfossil remains of the São Miguel scops owl date only from the Holocene, between about 50 BCE and 125 CE. It’s likely that it was extinct by the 1400s, following the settlement of humans in the Azores, destruction of its forest habitat, and the introduction of rodents, cats, and weasels.

Serpentisuchops

While the most iconic types of plesiosaur were long-necked with small heads and short blunt snouts, some of these marine reptiles actually developed the opposite sort of arrangement, with groups like the polycotylids and the pliosaurs independently evolving short necks, larger heads, and long snouts.

…Except some of them didn’t keep it quite that simple.

Serpentisuchops pfisterae here lived during the late Cretaceous, about 70 million years ago, in the ancient Western Interior Seaway covering what is now Wyoming, USA. This 7m long (~23′) plesiosaur was a member of the polycotylid lineage, but along with a long slender snout it also had an unusually long neck.

Some earlier polycotylids like Thililua had fairly long necks, too, but all of Serpentisuchops’ closest relatives were short-necked species, so it seems to have actually re-evolved this condition rather than inheriting it from its ancestors. Since no other marine reptiles in its habitat had this particular body plan, it was probably occupying a very specific ecological niche – the presence of attachment points for powerful neck muscles suggest it was able to swing its head sideways to snap its jaws at prey at high speed, with its longer neck giving it more reach than other polycotylids.

Feilongus

Feilongus youngi was a pterosaur that lived during the early Cretaceous (~125 million years ago) in what is now northeastern China.

Known only from two skulls and a few neck vertebrae, its full body proportions are uncertain, but it’s estimated to have had a wingspan of somewhere around 2.4m (7’10”). As part of the ctenochasmatid lineage it was probably a wader specializing in snagging aquatic prey between its interlocking needle-like teeth.

It had two bony crests on its head – a long low one along its snout, and a backwards-pointing one at the very back of its skull – along with a distinct overbite at the front of its jaws. These structures are only seen in the larger of the two known specimens, suggesting that they either only developed towards full maturity or that this species was sexually dimorphic.