Skull Diggery! Trivia Quiz

Answer: Caliper

Careful measurements of the outside of the skull can help paleoanthropologists determine how to classify their finds, and there are many formulas to apply. One of the formulas used is the Skull Proportion Index, which identifies the proportional value between the face and the cranium. Hominids would have a larger face and cranium than a modern human. To calculate, measure the cranial breadth and the facial breadth, divide the cranial breadth by the facial breadth, and multiply by 100.

The greater the value of the index, the larger the cranium is in relation to the face, and the older the find. Early hominids had a projecting, muzzle-like face.

It is also possible to measure what is called the Facial Projection Index by dividing the facial projection length by the total skull length and multiplying by 100.

The greater the value of the index, the greater the facial projection, and the older the find.

Answer: Hominid skulls are more elongated.

On the average, a hominid skull is much more elongated that a human; humans generally have rounder skulls. In measuring, paleoanthropologists use what is called a Cranial (or cephalic) Index. The cranial breadth is divided by the cranial length and multiplied by 100. An index of less than 75 indicates a long headed specimen; an index of 80 or more indicates a round headed specimen.

Answer: Palate

Hominid teeth are much larger than humans', so they also have a deeper palate. Just think for a moment about what hominids normally ate - which was anything they knew was edible that didn't kill them! Tubers, nuts, grasses, and the occasional lucky find of a dead animal were all part of their diet. They not only would need to chew for a very long time, but they would also have to have larger teeth to break their food down. The teeth can be measured using the Canine-Incisor Index; hominids would have a longer canine in comparison to the length of the incisor.

Answer: U

A human mandible is in the shape of a "C"; our teeth are smaller and farther apart. A hominid mandible would be more in the shape of a "U"; they had larger teeth that were closer together because of the nature of the food they ate. The size and shape of hominids mandibles changed dramatically over time, probably due to the development of tools for better preparation of food, and the use of fire for cooking. Large teeth were no longer a necessity.

Answer: To reinforce the weaker bones of the face.

The brow ridge, or supraorbital ridge, is more pronounced in hominids. Tremendous pressure was placed on the cranium as hominids chewed; the brow ridge served to reinforce bones of the face, much like chin bones do in humans today. The brow ridge was one of the last traits lost by hominids as they became human; although humans today have little or no brow ridge, it is still a noticeable trait among some people.

Answer: Foramen magnum

In hominids that were quadrupeds, the foramen magnum is located toward the back of the cranium; in bipeds the foramen magnum is more centrally located, as is shown in the picture. The Skull and Vertebral Attachment Index is used for this calculation, and shows whether upright walking occurred. Findings have shown that hominids as early as "Australopithecus afarensis", or "Lucy", were habitually upright walkers, as was the creature who is considered the first true human, "Homo erectus".

Answer: The creature had the ability to speak.

As hominids gathered into larger groups, a greater need for organized communication developed. Hunting plans could be discussed, and there was always new knowledge and invention to pass along. Hominids were probably using some sort of sign language for quite some time before they developed the ability for spoken language.

The Broca's area coordinates tongue, throat, and mouth muscles, enabling speech. Scientists can discover the size of the Broca's area in the brain by looking at the imprint on the inside of a cranium.

It is faintly identifiable in "Australopethicus" species, and becomes more distinct in "Homo erectus" and beyond.

Answer: True

Because skulls are usually found crushed with missing pieces, it is somewhat difficult to determine brain size. One method used in the past was to reconstruct the skull, make a cast, and then see how much water is displaced by the cast. Usually some sort of granular substance, like mustard seeds, is placed in the cavity, and measured in a flask.

Modern scientists have also found it is possible to use a CAT scan, which can create 3-D images and calculate the volume; there are studies that show the granular method may have overestimated the size of hominid brains a bit. For comparison: "Lucy's" ("Australopiethcus afarensis") cranial capacity was about 375 to 500 cm3 (cubic centimetres); a chimpanzee's brain is approximately 275-500 cm3; the Neanderthals' brain is approximately 1,500-1,800 cm3; and in modern humans a woman's brain is 1130 cm3, while a man's is 1260 cm3.

Answer: Later human like "Homo sapiens".

The skull would definitely belong to a "Homo sapiens". If you read closely, you know it belonged to a Neanderthal. Neanderthals were robustly made so that they could survive the very cold climatic conditions, and their brains were even larger than modern humans! Although they were pictured for a long time as communicating in grunts and gestures, Neanderthals had a very distinct Broca's area. We will never know how their language sounded, but they physically has the ability to speak.

Answer: Hominid

Hominids had the ability to walk upright, however, they were small-brained creatures with powerful jaws and large teeth. They probably would have had to communicate using grunts and gestures.