Thursday, January 24, 2019

Shadows on the Trail Meets Clovis Wandering

by John Bradford Branney

Figure One - Five High Plains Clovis spear points / knife forms surface found on private land.
Note that each of these points has a flute starting at the center of its base and ending in the body
of the point. Longest point is 3.85 inches long. John Branney Collection.  

Close your eyes and imagine the emptiness of North America thirteen thousand years ago. No cities, no towns, no highways, no planes. Not much of anything except a few bands of roaming Paleoindians spread across the expanse of a continent, living amongst a land of countless animals.
After its discovery and coronation in the 1920s and 1930s in New Mexico, Clovis became the royalty of North American archaeology. Scientists proclaimed the mammoth hunters who made the Clovis artifacts the First Americans, i.e. the first humans to ever walk on North American soil. Clovis technology has taken the breath away from artifact hunters and scientists alike. Books and magazine articles have fulfilled our insatiable appetite for Clovis artifacts and the Paleoindians who made them. No other prehistoric culture or technology in North America has drawn as much attention as Clovis.
Figure Two - Edward Howard at the
Clovis site in New Mexico in 1933.
We know from current archaeological evidence that Clovis technology started showing up in North American sites around 13,500 years ago. Where did the Paleoindians who made this technology come from? The first and the longest held belief was that Paleoindians, originating in Asia, crossed the Bering Strait from Siberia into Alaska during the last ice age when ocean levels were low. Since these Paleoindians were considered the First Americans, they either had to bring Clovis technology with them from Siberia or they had to invent it here. The Clovis First theory held water for decades and there are still a few scientists who hold it dear, but we have yet to come up with the "smoking gun" that proves Paleoindians crossed the Bering Strait bringing  Clovis technology with them.     

When it comes to Clovis technology, what is that smoking gun? Clovis technology is represented in the archaeological record by stone projectile points, prismatic blades, blade cores, and unifacial tools made from blades. Clovis technology was heavy into blade technology. Clovis technology also includes projectile points and foreshafts made from bone and ivory. Clovis technology is also associated with red ocher as these Paleoindians sprinkled the hematite-rich powder indiscriminately over artifacts and burials. Other Paleoindian cultures used the above technologies occasionally, so these were not unique to Clovis. However, there is one technological innovation that had a Clovis signature. The "smoking gun" that distinguishes Clovis from others is the "Clovis flute" on projectile points! 

Clovis projectile points are quite distinct, you might say they are one of a kind. Beyond their distinctive outline and flaking pattern, Clovis projectile points had another special feature; they had a flute or groove, starting at the center of the base and running toward the tip of the projectile point (figures one and three). Artifact hunters and scientists have found fluted Clovis projectile points across the lower 48 states. Artifact hunters and scientists have discovered Clovis or Clovis-like projectile points from coast-to-coast, from Canada to northern Mexico. This was an amazing dispersion of technology over a little more than three hundred years. Adaptation of Clovis technology must have been quick and decisive. Clovis or Clovis-like projectile points are one of the most recognizable projectile point type in North America. If Clovis technology came to North America through Siberia, why can't we trace Clovis technology back to Siberia?
Figure Three - 3.85 inch long Clovis spear / knife form surface
found on private land in Colfax County, New Mexico. Note the
extraordinary flute. John Branney Collection. 
A master flintknapper named Bob Patten once wrote, "If, as it appears, the Clovis tradition [fluting] was invented here [North America], someone must have already been here to invent it."

They say that hindsight is 20-20. To believe that there were no humans in North America prior to Clovis has always seemed naïve to me. Every other continent on the globe has evidence of humans going back tens or hundreds of thousands of years. How do we account for North America being human-free until around 13,500 years? How did North America stay isolated from the “Cradle of Man” in Africa for million or so years?
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Ninety years after scientists first documented Clovis in New Mexico, there is undeniable archaeological evidence in North America that Clovis people were not the First Americans. Perhaps, scientists were so locked into their ‘Clovis First’ theory that they poo pooed anything that disputed it. Perhaps, when they dug archaeological sites, they stopped digging once they found Clovis. In the past two decades, the "Clovis First" theory has taken severe blows and is down for the eight count and dead to some of us. Archaeological discoveries older than Clovis are aplenty, pushing human entrance into North America to 14,500 years, 15,000 years, 16,000 years, and beyond. It would not surprise me that some day soon archaeological evidence will prove early man was in North America over 50,000 years ago.
As far as the origin of Clovis technology, the mystery remains unsolved. In 2011, scientists excavated Clovis-like fluted projectile points at a site called Serpentine Hot Springs in northwest Alaska (Figure four). Was this the smoking gun everyone was looking for? Charcoal from the site dated around 12,000 years,  a thousand years younger than Clovis technology in the lower 48 states. If the Clovis-like fluted projectile points in Alaska originated in Siberia as the Clovis First theory contends, then the Alaskan points should be older than Clovis technology in the lower 48 states. Instead, the Clovis-like fluted points at Serpentine are one thousand years younger, possibly indicating that the Clovis technology dispersion direction was from the lower 48 states to Alaska, and not visa versa. 

Bottom line? We still have no smoking gun for the origin of Clovis technology.     
Figure Four -  Fluted points found buried in 
northwest Alaska. Charcoal dated the site
younger than Clovis in the lower 48 states.   

Wednesday, January 16, 2019

CROW AND THE CAVE - Prehistoric Limaces, Artifacts Named for Garden Slugs

Figure One - 3.5 inch long limace, surface found on private land in Yuma County, Colorado. John Branney Collection. 
"WHACK!” A massive paw exploded out of the blackness of the cave. A curved claw ripped the tip of Cansha’s nose wide open. Cansha’s eyes saw red as he felt the jolting pain. He grabbed his severed nose with both hands and fell backwards onto the pile of bones and half frozen feces. The sensation was horrendous. Tears flooded Cansha’s eyes. His hands filled with blood as he laid there in agony in the muck. His nose stung like the poisonous bite of a rattler. Blood escaped through his fingers. The man eater shoved its front leg through the gap, its claws outstretched, searching for flesh. The boulder wobbled back and forth as the huge beast pressed against it. Cansha rolled around on the ground as he fought to escape the pain. He could not see anything through blood and tears. He stood up and staggered on unsteady legs. He feared the beast would escape. A roar erupted from the cave. The boulder rocked further. The man eater’s leg squeezed out through the widening gap. Heesha kicked her father in the leg, waking him up. The thunderous call of the beast resonated across the plains. Heesha scrambled down the slope and reached her brother. She saw the blood all over Cansha. The claw had split Cansha’s nose right down the middle. Another roar from the man eater refocused Heesha’s attention. She watched in horror as the massive claw swiped at empty air. The boulder slid as the man eater pushed against it.
The above scene is from my latest prehistoric adventure titled the CROW and the CAVE. If you read my other prehistoric adventure books, you might be asking, "What kind of precarious situation did I put the Folsom People in this time?" You will just have to read CROW and the CAVE to find out. I promise you there are plenty of precarious situations from front cover to back cover.
Figure Two - an ordinary garden slug, 
or in France, a limace.  

Now onto my main topic…A slug in France, as in an ordinary garden slug, is known as a limace. Most of us have spotted a slug or two in our gardens or crawling across our sidewalks (Figure two). They are pretty nasty-looking creatures.   

What does this unattractive creature have to do with my books or archaeology? French archaeologists took their word for slug, limace, and described prehistoric stone tools that resembled the shape of a slug. Voila! The name stuck. A limace is a type of  prehistoric blade tool, retouched by its knapper along both edges, creating a slug-shaped artifact. A rather large limace from my personal collection is photographed in figures one and three. 
Figure Three - Cross sectional view of the limace from figure one. Note the plano convex profile and retouch
along the edges. John Branney Collection.  
Limaces are plano convex in cross section. Plano convex means that an artifact has a flat underbelly (ventral side) and a humped back (dorsal side). Another word to use for this is unifacial. Limaces are oblong or teardrop-shaped. Because of their defined purpose (I write about this later), limaces started out bi-pointed with sharp ends. Some limaces had steeply angled faces due to unifacial retouch, much the same as the "bit" or working end of a plano convex end scraper. Based on analyses, there is a high probability that prehistoric tool makers hafted the majority of limaces into a rigid socketed handle of bone or wood. Providing evidence for hafting, investigators pointed to the deliberate abrasions on the basal edges of some limaces and the ‘trim to fit’ dimensions on the proximal end of some other specimens.
Figure Four - 1.9 inch long limace surface found on
private land in Logan County, Colorado. They don't
get much more slug-like than this one.
John Branney Collection.   

Most investigators believe that prehistoric people utilized limaces as stone chisels for shaving and gouging hard materials such as wood, bone, and antler. Based on this harsh activity, it would not take long for the working end of a stone limace to look beat up and rounded. Limaces are a rare find and the destructive nature of their usage may be responsible for the rarity. It is tough to find a limace in excellent shape such as in figure one. I have probably surface recovered many broken and used up limaces, but not known what they were. I am sure prehistoric, conservation-minded people repurposed many broken and used up limaces into other tools, such as plano convex end scrapers.

In the literature, I have noticed other names for limaces or limace-like artifacts such as hump-backed scrapers, humpies, flakeshavers, awls, perforators, unifacial drills, slug-like scrapers, groover, slugs, bar, boats, Hendrix scrapers, and bipointed bars. This does not mean that every single specimen in the above artifact types was a limace, but that actual limaces might be mis-categorized in collections.

Michael Sampson studied limaces in the Tulare Lake Basin, between Bakersfield and Fresno, California. In his paper, Humpies, an Unusual Flaked-Stone Tool Type from the Tulare Lake Basin, he proposed that true limaces, or “humpies” as he called them, were diagnostic artifacts of Paleoindians, at least in the Tulare Lake Basin. He noted that investigators had found humpie-like
Figure Five - 4.9 inch long blade surface found on private land in central Wyoming. It could be a 
rather large limace or maybe a "hump-backed" whale ;). John Branney Collection.   
artifacts in both Siberia and Japan, dating to pre-Clovis times. Sampson also noted at least five other well-documented Paleoindian sites where investigators found limaces or humpies; the Shoop Site in eastern Pennsylvania, the Debert Site in Nova Scotia, the Bull Brook Site in Massachusetts, the Vail Site in Maine, and the Lehner Mammoth Kill Site in southern Arizona. Other sites reporting limace or humpie-like artifacts include Plenge, Lindenmeier, Whipple, Shawnee-Minisink, and Krmpotich.

Based on current archaeological evidence, it appears that “true” limace tools were most likely associated with Paleoindians and large Folsom, Clovis, and fluted point assemblages.

Now, why don't you support this starving author and buy / read the SHADOWS on the TRAIL QUADRILOGY?  



Thursday, November 8, 2018

Part Three, an Atlatl Spur and SHADOWS on the TRAIL QUADRILOGY

Figure One - 2.2 inch long granite atlatl spur found on private land
in Kings County, California by Connie Hudson prior to 1970.
John Branney Collection.  

The finger bone's connected to the hand bone,
The hand bone's connected to the arm bone,
The arm bone's connected to the shoulder bone,
Now shake dem skeleton bones!

Dem bones, dem bones gonna walk around
Dem bones, dem bones, gonna walk around
Dem bones, dem bones, gonna walk around
Now shake dem skeleton bones!
When I think about the process of using an atlatl weapon system, the above song comes to mind. Many of us have sang that song. The various muscles and bones in the human body must work together in unison and harmony, and to make a successful atlatl throw, various components in the atlatl weapon system must work together in unison and harmony. One big difference between the atlatl and human body is that in the atlatl process one of the components detaches from the rest of the components; the atlatl dart. We better hope that we don't have any detaching components in the human body!  
Figure Two - Atlatl mechanics. 

Most experts believe that prehistoric humans had access to the atlatl weapons system in North America as far back as Paleoindians. Archaeological evidence for this is circumstantial. However, we do have clear evidence that the atlatl was in play in North America as early as the Middle Archaic. Based on archaeological evidence, bow and arrow technology replaced atlatl technology in North America sometime around A.D. 200 to A.D. 500. However, there were some atlatl holdouts. When Spanish explorer Hernán Cortés landed in Mexico to conquer the Aztecs around 1519, he found the atlatl in use within the Aztec population. Cortés also found out that Spanish chain mail armor wasn't always effective against the penetration of an atlatl-thrown dart.

Figure Three - Close up of an atlatl dart, seated on a spur which
connects the dart to the handle. 
An atlatl handle is a piece of wood, bone, or antler two feet long or so. The purpose of the atlatl weapon system is to extend the arm of the thrower much like a lever. When thrown properly this increases the velocity of the thrown dart (see links below for my other blog postings on the subject).   One end of the atlatl handle was for the thrower's hand while the other end connected to the atlatl dart via a peg, hook, or spur. A cup at the end of the atlatl dart fit onto the spur of the atlatl handle. 
Figure Four - Rounded and
polished tip of the hummingbird spur. 
I will be referring to the peg, hook, or spur as simply the spur. As mentioned, the spur fits onto the atlatl handle and connects the atlatl dart to the atlatl handle. The spur and atlatl dart work on the same premise as a ball and socket. A ball and socket is a mechanical connection where the ball (in this case the spur) rotates in a socket (in this case the cupped end of an atlatl dart) allowing rotary motion within certain limits. In other words, the cupped end of the atlatl dart rotates on the point of the spur until it disengages from the atlatl handle during the throw. The dart stays engaged to the spur during the throw because the atlatl handle is traveling at a faster rate than the dart. When the user begins his throw, his arm pulls the atlatl handle forward and upward, and the cupped end of the dart rotates on the point of the spur until the dart disengages from the atlatl handle on its way to the target. 
Figure Five - Certificate of Authenticity from 
Robert Butler. 

Prehistoric and historic atlatl users made atlatl spurs from bone, rock, antler, and wood. There is one case in prehistoric Colorado where investigators believe a bison tooth was used as a spur. While prehistoric humans made atlatl handles and darts from mostly perishable materials,
atlatl spurs tended to be the least perishable part in the weapon system. Investigators and collectors have found evidence for the use of the atlatl in California in most every region of the state in the form of atlatl spurs. In fact, California has enough prehistoric atlatl spur examples to classify them within categories. (Ralston and Fitzgerald 2014).
Figure Six - A mock up of how I believe this
bird head spur was used.  
Figures one, four, and five show an example of a prehistoric atlatl spur found in Kings County, California by Connie Hudson prior to 1970. Robert Butler certified this as a museum grade atlatl spur (figure five). Most of the people I have spoken to who have knowledge about atlatl spurs believe this spur represented a bird's head. One person went as far as to claim that the bird's head was a hummingbird. 

A bird's head would be an ideal symbol for an atlatl. If we think about an atlatl dart flying effortlessly through the sky, what better symbol for a successful flight than a bird or hummingbird. The drawing in figure six represents how I believe the hummingbird atlatl spur was implemented. Check out my books at the end of this article!   

2014    Candice Ralston and Fitzgerald, R. T. Two Atlatl Engaging Spurs from CA-CCO-18/548: A Critical Examination of Atlatl Spur Taxonomy. Journal of California and Great Basin Anthropology 34(1):101-108. 



Tuesday, October 9, 2018

Clovis Ovate Biface or Folsom Ultrathin Knife in SHADOWS ON THE TRAIL

Figure One - 3.5 inch long semi-translucent biface
surface found in Wyoming. John Branney Collection.  
There is a good chance that the biface in Figure one is an ultrathin knife form from the Folsom prehistoric culture (10,900 to 10,200 years old). The late Jim Roth surface recovered this artifact on private land in Carbon County, Wyoming. For those of you who have read my prehistoric adventure series about the Folsom People, the popular SHADOWS ON THE TRAIL QUADRILOGY, my main character Chayton and other hunters in his tribe carried ultrathin knife forms to filet meat from the prey animals they butchered. Below is a short scene from the second book in my prehistoric adventure series, GHOSTS OF THE HEART. In this scene Chayton and the hunters had trapped and killed a small herd of now extinct bison. In this episode, the hard works begins - butchering.  

When it was all over, the tribe had killed twenty-two tatanka – bison. The meat from the herd would help the tribe through wani yetu – winter. One of the hunters ran to the camp to tell the people of the tribe. Before long, the entire tribe had returned to help butcher and carry the meat back to the camp. First, everyone in the tribe helped lay all of the carcasses on their bellies with legs sprawled. Then a team of two or three butchers worked on each carcass; while one person held and positioned the carcass, the other person chopped, sawed and cut. The team of butchers
Figure Two - CLICK to ORDER
then cut the hide lengthwise down the back. They then pulled the hide to the ground on both sides of the carcass, creating a mat that would protect the butchered meat from the ground. The team of butchers extracted the tender cuts of meat under the skin of the back first, followed by the forelegs, shoulders, hump meat, rib cage, and body cavity. They would not waste anything. The team of butchers opened up each body cavity and removed the heart, liver, and gall bladder.  

With hammer stones, choppers, and stone knives, the butchers then harvested the hindquarters, hind legs, neck, and skull. As the team of butchers systematically stripped the meat from the carcasses, others carried the meat back to the camp where they cut it into strips and hung it from sagebrush and tree branches to dry. The Folsom People would make pemmican from the meat that was too tough to eat. They then extracted two more delicacies from the skull, the tongue and the brain.  

I hope you will join the adventure and read my book series, the SHADOWS ON THE TRAIL QUADRILOGY. You will be glad you did. 

Now, what do you think about this knife form? Is it Folsom or could it be Clovis? 

1. The dimensions of this knife form are as follows;  it is 88 mm long, 42 mm wide, and 5 mm thick. The width to thickness ratio is 8.4. The arbitrary width to thickness ratio for ultrathin knife forms is 7 or greater. 

2. The raw material is wild. A beautiful semi-translucent, banded petrified wood was used by its maker. 
Figure Three - 3.5 inch long biface surface found in Wyoming.
One edge of the biface was polished smooth, indicating to me
this was used hand held. Note diving flakes near middle
of biface. John Branney Collection.   

3. In several flake terminations, there appears to be oxidized red ochre stains and deposits. Ochre is a natural mineral containing ferric oxide. It is typically associated with clay and varies in color from light yellow to brown to red. Red ochre has been found in many different archaeological contexts including occupations, especially Paleoindian occupation floors. Stone artifacts were painted with the red ochre and sometimes weapons and tools were covered in the pigment. It has also been associated with burials. Red ochre was widely used at Paleoindian levels at the Powars II, Hanson, Hell Gap, Sheaman, and Medicine Lodge Creek sites in Wyoming. Investigators discovered a grinding slab used for pulverizing red ochre nodules and rocks in the Folsom level at the Agate Basin site in eastern Wyoming. 

Note: I have NOT had this knife form chemically tested for the presence of iron or ochre. My assumption as to the presence of ochre is based on experience and observation of the deposits under high magnification.

4. We know prehistoric people used different types of ochre for paint pigment and we assume they used it for ritualistic purposes. Upper Paleolithic graves in Europe and at least one Clovis grave in the United States contained ochre. Ochre appeared to have an application in the Magdalenian in Europe as an ingredient in an adhesive that was used to haft knife forms and projectile points to handles and foreshafts. Perhaps, North American Paleoindians used red ochre for the same thing to haft points and knives. That would 
Figure Four - Red ochre in its natural state. 
explain the occurrence of red ochre in the hafting area of many Clovis projectile points. Some investigators also believe that Paleoindian flintknappers in North America might have used red ochre as an abrasive to polish and dull the lateral edges in the hafting areas of projectile points. Dulling the edges was a common practice in Paleo and Early Archaic times.
Red ochre is also commonly found with Clovis tool caches but it is not known whether the occurrences were functional or ritual.    

5. It is not coincidently that the predominant colors used in rock art and cave art in the Old World and in some cases, New World, were black (from charcoal, soot, or manganese oxide), yellow ochre (limonite), red ochre (hematite or burned limonite) and white (kaolin clay, burnt shells, powdered gypsum, or powdered calcium carbonate). 

Figure Five - Clovis biface thinning sequence. 
6. I love Paleoindian flintknapping, especially their biface thinning through percussion technology. The flaking on the artifact in figures three and six screams Paleoindian. Paleoindians liked to attack a piece of flint with carefree but skilled abandon. The Paleoindian flintknapper's attitude was "why thin a biface with ten swings of the hammer when five swings will accomplish the same result?"  Paleoindians thinned bifaces with wide, thin flakes that crossed the face of the biface, sometimes overshooting the other edge (see figure five). The end result was wide, thin, and long flakes that were exceptionally flat which thinned the biface without losing overall length or width.
5. On the artifact in figures three and six, several of these wide-thin-flat flakes terminate midway across the face of the biface, creating step or hinge terminations in the middle of the artifact. These diving flakes created a biconcave cross section for this knife form. Some of these diving flakes were met by diving flakes from the other side, creating an even more concave profile in the middle of the artifact.

Figure Six - Reverse side of 3.5 inch long biface. Note diving flakes near 
middle of biface. John Branney Collection.    

Few knife form or biface types are culturally diagnostic. It usually takes finding them in situ under a controlled archaeological process to determine age and cultural affiliation. This knife form was a surface find and I assume it was Folsom or Clovis, based on its production technology, knapping characteristics, and the presence of oxidized red ochre. But, just because that is what I think does not make it necessarily so. This is my opinion on this truly unique knife form.

So, what is your opinion? Is it a Clovis Ovate Biface
or a Folsom Ultrathin Knife or maybe something else?


Thursday, September 27, 2018


Figure One - Photo of a painting called Pre-Columbian Indian with Atlatl by well-known western artist James Bama. 

In Part One of Atlatl and SHADOWS ON THE TRAIL QUADRILOGY, I discussed the concept of the atlatl and the advantages gained by artificially lengthening the throwing arm. With everything else being equal, lengthening the throwing arm through the effective use of an atlatl increases the velocity and distance of a thrown spear or dart. Higher velocity translates to more damage to the target. However, there is an optimal limit to the length of an atlatl and increasing the length beyond that optimal limit decreases accuracy.  

Before we discuss Part Two of Atlatl and SHADOWS ON THE TRAIL QUADRILOGY, I will take you on a very brief hunt from my first book, SHADOWS ON THE TRAIL. In this scene, our hero Chayton is hunting elk with an atlatl. The year is 8700 B.C.  
Figure TwoCLICK to ORDER
Chayton’s weary head pounded as he impatiently waited for the animals’ next move. Then, he realized he was breathing too fast and too loud; they may hear him. He slowed his breathing down and grasped the spear shaft in his hand. He placed the butt end of the spear into the notch of his spear thrower. Then, breathing very slowly, he waited.

Two majestic elk, a young bull and a cow, walked out from behind the trees, heading straight at Chayton. The bull led the way while the cow followed behind. The elk held their heads high and sniffed at the air, smelling for any danger that would set them off running. The elk, upwind from Chayton, did not pick up his scent and kept walking towards him.

Chayton’s left throwing arm was cocked and ready to throw the first spear, but the bull was still walking straight at him. Chayton did not like his chances for a kill with this throw. The bull had no vital organs exposed to Chayton’s line of fire and unless Chayton threw perfectly and severed an artery, the elk would not go down. The last thing Chayton wanted to do was track a wounded elk in this rugged country.
Chayton needed the elk to turn and expose its side to his spear. Chayton thought about moving, but one sound and he would send the elk crashing through the trees in the opposite direction. The elk continued to walk straight towards Chayton. Any closer and they would pick up Chayton’s scent.

Chayton searched the ground with his right hand and found a small rock. While his left arm kept his spear ready to throw, he hurled the rock to his right where it ricocheted off a tree. The bull reared back and ran away from the sound, exposing the left side to Chayton's spear. Chayton hurled the spear…
What happened with the elk? You will have to read the SHADOWS ON THE TRAIL to find out. Don't worry, this journey is well worth your time.  

In Part Two of Atlatl and the SHADOWS ON THE TRAIL QUADRILOGY, I explore the flight of the atlatl-launched spear or dart, but first a little housekeeping. In the following paragraphs, I will refer to the projectile that leaves the atlatl as a spear, even though some literature refers to the same projectile as a dart. In Part Two, atlatl spear and atlas dart are one and the same. 

The basic mechanics of an atlatl system depends on the flexibility of the spear. When the atlatl pushes the spear forward (figure three), energy is transferred from the atlatl and stored in the spear much like a spring. When the spear lifts off from the atlatl, the stored energy is released and converted to additional velocity as it flies toward the target.  
Figure Three - The ingenious mechanics behind the atlatl is the stored energy within a flexible spear. 

Two concepts from physics help us to better understand the flight of an atlatl-launched spear. The first concept is momentum. Most of us have used the term momentum, perhaps to talk about our favorite sports team or maybe a political race or any of a hundred other reasons. In physics, momentum is defined as the tendency of an object to continue moving in its original direction. Momentum is an object’s resistance to stopping. An example of momentum is a rolling freight train that suddenly needs to stop. The freight train's momentum takes the train past where it should be stopping.  
How do we calculate momentum? Momentum (P) is equal to the object's mass (M) multiplied times (x) the object's velocity (V). As an example, if a light atlatl spear is flying through the air at the same velocity as a heavy atlatl spear, the light spear has less momentum than the heavy spear. Put in a different way, less resistance is needed to stop a light spear if traveling at the same velocity as the heavy spear. Change either mass or velocity of an object and its momentum changes.   

Momentum = P = M x V

As you can see from the above equation, mass and velocity carry the same weight when calculating momentum. Based on the equation, a slow-moving heavy spear can have the same momentum as a fast-moving light spear.   
Figure Four - Middle Archaic atlatl dart points showing size ranges. Longest point is 1.9 inches long.
John Branney Collection 
The other physics concept is kinetic energy which is the energy of an object in motion. The more kinetic energy a spear has, the more available energy it has to penetrate the animal's hide, break bones in its path, and push the projectile point and spear shaft into the prey's body cavity.    

Just like momentum, kinetic energy is defined by an object’s mass and velocity, except mass and velocity affect kinetic energy differently. While mass and velocity carry equal weight in momentum, velocity is much more important and mass is much less important with kinetic energy

Kinetic energy (KE) is equal to one-half times mass (½ M) multiplied times (x) velocity squared (V²).

Kinetic Energy = KE = ½M x V²
To calculate kinetic energy, we cut mass in half and square the velocity!  
In my previous example, I mentioned that a slow-moving heavy spear can have the same momentum as a fast-moving light spear. However, the fast-moving light spear has much more kinetic energy than the slow-moving heavy spear. Velocity has a much higher influence on kinetic energy than it does  momentum. If the heavy spear and light spear are flying at the same velocity, the heavy spear has more kinetic energy because it still has more mass.  Although mass is important when it comes to spears, velocity has a huge performance effect on distance, momentum, kinetic energy, and accuracy. The atlatl itself has no impact on mass but it has a huge effect on increasing velocity.

Figure Five - Paleoindians carrying atlatls and spears. 
Is a heavy or a light atlatl spear more lethal when it comes to hunting? Whittaker, Pettigrew, and Grohsmeyer (2017) explored the  relationship between heavy and light atlatl spears and suggested  that Paleoindians who hunted large mammals such as mammoths or bison required heavy spears and projectile points. The spear had to be able to cut a hole through the animal hide with enough momentum to reach vital organs and/or cause lethal hemorrhaging. Try to imagine hunting a mammoth with a light spear and small projectile point. That would be like “hunting a bear with a switch”. Although it is not prudent to hunt mammoth with undersized equipment, that same equipment is probably suitable for hunting wary antelope on the plains where adding velocity improves distance and accuracy.  

I believe that Paleoindians customized their atlatl weapon systems for the type of game they expected to encounter. If the targeted prey were mammoth or bison, the spears and projectile points were accommodated. If the targeted prey were deer, antelope, or mountain sheep, the spears and projectile points were lighter and took advantage of velocity. This is not any different than what we see modern hunters doing. You don’t see experienced hunters using their elephant rifle on antelope or visa versa.     
2017    Whittaker, John C., Devin B. Pettigrew, and Ryan J. Grohsmeyer
Atlatl Dart Velocity: Accurate Measurements and Implications for Paleoindian and Archaic Archaeology in Paleoamerica, Vol. 3, No. 2, pp. 161-181. College Station.     

CLICK here in CASE you MISSED Part ONE of my ATLATL Article   

Hey, and check out my books, will ya?