Adalatherium

## AdalatheriumCrazy Beast

* **Skull Length** of 8.4 centimeters (3.3 inches)
* Front of skull has more openings than that of any other mammal except *Vincelestes*

***“ Simosuchus is not the only evolutionary oddity to thrive on Madagascar. The island is also home to another group of very unusual animals... Mammals. This is a female Adalatherium. She's less than two feet long, but even so, she's still one of the largest mammals to have yet evolved. ”***

― **David Attenborough**, *Islands*
***Adalatherium*** (Crazy Beast) is an extinct gondwanatherian mammal that lived in the Maevarano Formation, Madagascar, 70 - 66 million years ago, during the Maastrichtian stage of the Late Cretaceous Period.

## Description

Out of all the Mesozoic mammals known so far, the badger-sized *Adalatherium* is the third largest in terms of mass, only exceeded by *Vintana*, a groundhog-like mammal that lived alongside *Adalatherium* in the Maevarano Formation, and *Repenomamus*, a dinosaur-eating carnivore lived in the Yixian Formation in China more than 50 million years before *Adalatherium*. The front of its skull (the second discovered head of any gondwanatherian mammal, the first being that of *Vintana*) also has more foramina (openings) than that of any other mammal except *Vincelestes*. Fitting for its size, Prehistoric Planet depicts *Adalatherium* as quite a stocky mammal, covered in short fur that is light brown over the head and back, with the underbelly and neck colored light tan. It is also shown with decently-sized claws that dig through the soil to form or enlarge new or preexisting burrows, or uncover roots and seeds to feed on. The cubs are born naked and blind, and rely on milk produced from modified sweat glands on their mother's belly.

## Habitat

*Main: Maevarano Formation*

Main: Maevarano Formation

***“ The island of Madagascar has been separated from the African mainland for 80 million years, so long that most of its animals are now very different from any to be found elsewhere. ”***

― **David Attenborough**, *Islands*
*Adalatherium* lived 70 - 66 million years ago in the Maevarano Formation in the Mahajanga Province of Madagascar. The Maevarano Formation is recognized as an alluvial plain where the discharge of rivers fluctuate. The area is also believed to have had reddish soil, with floodplains that supported vegetation able to grow in the relatively dry climate. The region, at times semi-arid (like it is today), at times undergoing strong dry and wet seasons, was eventually claimed by rising sea levels that pushed the shoreline back. This may or may not have been the result of the Cretaceous-Paleogene Extinction Event, a catastrophe that wiped out three-quarters of life on Earth.

## Behavior

***“ She spends most of her waking hours searching for food. At the end of the tunnel, there are eggs, potentially a rich source of protein. But she doesn't eat this particular clutch. These are her own eggs, and this is her burrow. ”***

― **David Attenborough**, *Islands*
Prehistoric Planet depicts *Adalatherium* as a caring mother keeping her eggs safe in a hidden burrow. As the cubs of her litter (depicted in the show as reaching at least ten) grow, so do their appetites, so until the day that they can live independently, the mother has to exert more and more effort in finding food to feed herself and thus provide her cubs the milk they need. Since *Adalatherium* is a burrowing animal, it has poor eyesight, compensated by acute hearing. In the event that it comes across a threat, it tries to avoid getting noticed by staying completely still. And should the mother feel that her litter is living in an area full of danger, rather than continuing to risk living in the area, she and her litter would resort to moving somewhere else.

As for the cubs, born from small eggs, grow rapidly and rely on their mother's milk for a long time. They are also shown to be quite playful, clingy to their mother, and sleepy. Whenever their mother leaves to find food, the cubs stay within the safety of the burrow.

The idea that *Adalatherium* (and other gondwanatherians) laid eggs is a matter of debate. Based on the idea that multituberculates (which are considered close relatives of the gondwanatheres) might have laid eggs, *Adalatherium* was portrayed on the show as an egg-laying mammal. However, in a study published in 2022, just a year before the release of Season 2, an analysis of multituberculate bones suggested that multituberculates did not lay eggs, though the show's portrayal is not fully invalidated since it is still possible that gondwanatheres were different and not even closely-related to multituberculates.

## Appearances

### Islands

In the fourth segment of the episode, as the afternoon sun shines down on Madagascar, an *Adalatherium* travels across the land, making her way to a burrow obscured by the exposed roots of a tree. She comes across eggs within the den, and, sniffing them, she lies down and sleeps next to them, for these eggs are her own. The eggs hatch, and the juveniles, though born blind, sense where their mother is and feed on milk produced by modified sweat glands on her belly. In two months, the ten cubs have grown to more than four times their size, though still reliant on their mother's milk, so every night, she leaves the burrow to feed in order to be able to produce this nourishment. In the darkness, a serpentine figure watches her as she looks for sustenance, navigating the terrain decently, her acute hearing serving as compensation for her poor eyesight. She comes across the same injured, half-blind *Majungasaurus* that tried and failed to hunt some *Simosuchus* earlier in the day. In the presence of danger, the *Adalatherium* stays still to avoid getting noticed. Fortunately for the mammal, the theropod remained unaware of her presence, the *Majungasaurus* briefly sniffing the air before wandering off to continue looking for prey. When she is sure the predator is no longer around, she returns to digging the soil for roots and seeds to feed on.

***“ The cubs are growing fast, and so are their appetites. The female is now having to search almost nonstop for food, so her cubs are left unguarded for hours at a time. ”***

― **David Attenborough**, *Islands*
In the morning, after they suck milk from her yet again, the mother leaves her cubs in the burrow to search for food. Just then, a *Masiakasaurus*, also seeking food, pokes its narrow head and long neck through holes that could potentially contain a meal. However, just as the *Masiakasaurus* stalks around the tree roots just outside the burrow, close to discovering the oblivious cubs, the snake from the night before lunges at the theropod's throat, subduing its victim with its muscular coils.

***“ Madtsoia, a snake nearly 25 feet long, squeezes its prey to death. This neighborhood has now become rather dangerous. As night falls, the mother leads her young out of the burrow for the very first time. For now, at least, they must stay close together. ”***

― **David Attenborough**, *Islands*
Having bore witness to one potential predator kill and feed on another, just outside her burrow, the returning *Adalatherium* enters her den, settling down and letting her babies suckle on her. Deciding that the area has become too unsafe to live in, she moves out of the burrow and sets out for a better place to live in, her ten cubs following close behind. One of the cubs briefly looks back and finds the *Madtsoia* resting on a fallen tree branch, staring back at it. With this, the *Adalatherium* cub turns back around and continues to follow its mother as they leave the area.

### Prehistoric Planet: Uncovered - What Else Lived Alongside The Dinosaurs?

  **What Else Lived Alongside The Dinosaurs?**
**Subject**
The other weird and wonderful creatures that lived alongside the dinosaurs, from *Beelzebufo*, marine reptiles, and pterosaurs, to their successors, mammals.

**Experts**
Dr. Darren Naish, Dr. Marc Jones, Dr. Mark Witton, Professor Anjali Goswami
Footage of *Adalatherium* is used in the last portion of this Uncovered segment, dedicated to discussing the animals that lived alongside the dinosaurs. While many of the impressive creatures that lived alongside the dinosaurs (from massive frogs like *Beelzebufo* to the marine reptiles that dominated the sea and the pterosaurs that ruled the skies) were not like anything alive today, there were also some other animals that might seem a little bit more familiar.

The Late Cretaceous, though mostly remembered for the dominance of the dinosaurs, was also filled with mammals of all sorts, some of which lived in the water like beavers, critters that ran in the trees, gliding creatures, and even digging, burrowing animals like *Adalatherium*. Some of these mammals have even evolved for a nocturnal lifestyle, which helps them avoid some of the dinosaurs that lived alongside them.

***“ They evolved a lot of different tools to help them survive during that period. Fur, being warm-blooded, even evolving big brains and sensory structures that allow them to see at nighttime. In fact, we may have dinosaurs to thank for the way mammals look today. ”***

― **Anjali Goswami**, *Research Leader, Palaeobiology*
And as the reign of the dinosaurs, spanning more than 150 million years, was finally ended by a massive meteor strike, mammals took over as the dominant life on Earth, as they still are today.

## References

### General

1. ↑ Craniofacial morphology of *Adalatherium hui* (Mammalia, Gondwanatheria) from the Late Cretaceous of Madagascar

### Dr. Darren Naish

1. ↑ While there is no direct evidence for the reproductive behavior of *Adalatherium*, with some experts divided regarding whether they laid eggs or gave birth to live young, the show ultimately following through the decision to portray the animal as egg-laying, with a strategy different compared to those of egg-laying mammals today.
2. ↑ While multituberculates may not have laid eggs, the same may not necessarily be true for gondwanatheres, which may not be closely-related to multituberculates at all.