Mononykus

## MononykusSingle Claw

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***Mononykus*** (Single Claw) is a genus of alvarezsaurid theropod dinosaur that lived in the Nemegt Formation, Mongolia, 70 million years ago, during the Maastrichtian stage of the Late Cretaceous Period.

## Paleobiology

### Size and Physique

While it is one of the larger alvarezsaurids, *Mononykus* is still a very small animal, barely 60 centimeters (two feet) tall, around 1.2 meters (four feet) long, and weighing a measly 3.5 kilograms (7.7 pounds).

***“ She now uses the weapon that gives this hunter its name. Mononykus, 'single giant claw', just what she needs to open a termite's nest. ”***

― **David Attenborough**, *Deserts*
As per its name, each of its stubby arms only have a single 7.5-centimeter (3-inch) claw, much like the most alvarezsaurids (though some alvarezsaurids possess two vestigial fingers alongside their main claws). It is believed that alvarezsaurids used these peculiar limbs to break into ant and termite colonies, much like anteaters today, though there is also a theory that alvarezsaurids were nest raiders that used their claws to crack eggs open, evidence of which is seen when a *Qiupanykus* is found with some oviraptorid eggshells.

### Senses

***“ Mononykus is a desert specialist. Like many desert animals, she must patrol a huge area if she is to find enough food. Bare legs help keep her body cool. Feathers on her body shield her from the sun's rays, and they provide her with a super-sense. They form facial discs that help her detect the faintest of sounds. ”***

― **David Attenborough**, *Deserts*
*Shuvuuia*, a smaller alvarezsaurid that lived in Mongolia 75 million years ago, showed evidence of a shaggy, feathered coat. With its large sclerotic rings indicating sharp eyes with remarkable night vision and asymmetrical ear size for enhanced hearing (said to rival those of a modern-day barn owl), *Shuvuuia* is also believed to be a nocturnal hunter with its notable sensory adaptations.

Due to being one of the closest relatives of *Mononykus*, Prehistoric Planet applied the traits seen in *Shuvuuia* to its depiction of *Mononykus*, even giving it a barn owl's white and light brown color scheme and facial discs. It is also shown with a long, flexible tongue "twice the length of her head" like that of an anteater, based on the fact that another alvarezsaur is shown to have an advanced hyoid and toothless lower jaw tip. *Mononykus* is also depicted with some aspects of the similarly-built roadrunner, another sleek, small, feathered insectivore that dwells in the desert.

## Paleoecology

### Paleoenvironment

*Main: Nemegt Formation*

Main: Nemegt Formation

***“ Making the most of fleeting chances is key to surviving in the desert, and some dinosaurs manage to do so very effectively indeed. ”***

― **David Attenborough**, *Deserts*
*Mononykus* lived 70 million years ago in the Nemegt Formation, an area that would one day become the Gobi Desert in Mongolia. The formation shows evidence of a rich, humid environment with large river channels, tidal flats, and forests. However, the area is also known to have undergone periodic droughts, and there is precedence for arid regions much like the Gobi Desert today existing in Mongolia during those times, thus somewhat justifying the depiction of *Mononykus* living in or at least traveling through a vast desert environment, though the extent of it being a "desert specialist" is unknown.

### Behavior

***“ And with the vegetation comes an abundance of food... if you know how to catch it. ”***

― **David Attenborough**, *Deserts*
*Mononykus* is shown to be a competent hunter, pinpointing and breaking through a termite nest in a dead tree, and understandably shows irritation when termites crawl on her face, frantically scratching her face against the log and with her feet. She also shows some curiosity and confusion when she ends up in an unfamiliar environment, a temporary patch of vegetation in the desert, running around the place and viewing it from multiple angles, checking out a scorpion and deciding it might be too weird and dangerous-looking to eat, and even trying to catch enanthiornithine birds that are "perhaps a little too big to tackle".

*Mononykus* also exhibits caution, as shown when one hides in a small cave in the rocks when the rains fall (since she may have never witnessed such rainfall before), and when one darts between the legs of Mongolian Titans, moving away from incoming feet and occasionally stopping for a brief period to observe and judge what direction is it best to rush in next.

## Appearances

### Deserts

#### Segment 3

  **Deserts**, Segment III
**Setting**
Nemegt Formation, Gobi Desert, Mongolia

The third segment of the episode shows a female *Mononykus* traveling through the desert, looking for a meal. With her hypersensitive directional hearing, *Mononykus* is able to track down the faint sounds of a termite nest in a hollow log. Making her way onto the dead tree, she uses her hearing to mentally map out the termite nest and determines the right position to dig through, breaking a hole through the wood with her left claw. She sticks her long tongue through the wood and licks up some termites, though some do crawl on her face in the process, prompting her to shake and scratch off the irritating insects on the log and with her feet. When a storm suddenly forms in the desert, *Mononykus*, who has likely never seen such an event unfold to such an extent before, ran for shelter, taking refuge in a small cave in the rocks. The rain brings to life seeds that have long lied dormant beneath the ground. When the rains subsided, *Mononykus* rushed out, curiously looking for food through the vegetation, checking out trees, a scorpion, and even charging after eniantiornithine birds, which fly off as soon as she reached them. Running around some more, she eventually manages to find and grab a beetle, before rushing off, presumably to find more food. Eventually, the plants are wiped out and reverted back into an arid landscape.

#### Segment 4

**Deserts**, Segment IV
**Setting**
Nemegt Formation, Gobi Desert, Mongolia

**Filming Location**
Namibia, Southern Africa
In the fourth segment of the episode, a temporary oasis formed by rain attracts several animals of every kind from many miles away, including several *Mononykus*. A few of them riskily dart and weave between the legs of the Mongolian Titans and other massive animals that came to visit the oasis.

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## Trivia

It is unknown how exactly dinosaurs drank water. Prehistoric Planet chose to depict various types of dinosaur drinking water in different ways, with theropods shown scooping up water with their lower jaws rather than lapping it with their tongues or sucking it up. In the fourth segment of Deserts, *Mononykus*, *Therizinosaurus*, and *Tarbosaurus* drink water in this manner, and *Tyrannosaurus* is later depicted doing the same in the second segment of Freshwater.

## References

1. ↑ 1.0 1.1 1.2 *The Princeton Field Guide to Dinosaurs* (2nd ed.)
2. ↑ A new alvarezsaurid dinosaur from the Late Cretaceous Qiupa Formation of Luanchuan, Henan Province, central China
3. ↑ Evolution of vision and hearing modalities in theropod dinosaurs
4. ↑ Evidence of long tongues in alvarezsaurids
5. ↑ BTS: Apple TV+'s Prehistoric Planet