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Squirrel wonders (and the failure of evolution to explain them)

One of the most abundant wild mammals living in moderate latitudes is the common squirrel. Squirrels thrive in almost every habitat, from tropical rainforest to semiarid desert. They avoid only the cold polar regions and the driest deserts.

Squirrels are also one of the very few mammals that thrive in cosmopolitan areas. Some wild squirrels have even become pets of a sort, or at least comfortable around people, if the human is patient and not aggressive towards the animal.1 As two of the leading squirrel authorities observed, “one can only marvel at how well adapted squirrels are to exploiting a forested environment” and, one could add, an urban environment as well.2

Their diversity is enormous and the squirrel family includes, not only tree and ground squirrels, but also flying squirrels, chipmunks, marmots, groundhogs and prairie dogs, all which deserve a separate paper. Many of the 273 squirrel species live in North America where they have very few enemies. This paper covers only tree squirrels, which nest and live in trees and have bushy tails to help them balance while running up and down trees. Ground squirrels live on the ground, have shorter, less bushy tails, and their fur is usually brown-gray with gray and white dots.

Extremely well-designed

Squirrels are very well designed for their terrestrial and arboreal life. Growing up in Michigan, I remember tree squirrels moving on the ground by a “hopping run” travel mode to scurry up a tree. Their sharp claws enable them to run down the tree about as fast as they can run up it. Their trademark is their slender bodies with very long, very bushy tails.

The term “squirrel” derives from the bushy tail, which is one of their more-defining traits. Their large eyes give them excellent vision, allowing them to jump from one limb to another limb of the same tree, or even to other trees. They are one of the few mammals, aside from primates, that have color vision.2

Their excellent sense of touch uses the vibrissae (whisker-like hairs) on their strong flexible limbs as well as their heads. This system allows then to navigate telephone wires with ease, even while running on a wire almost as rapidly as they run on the ground.

A talented tail

Their tail is central to maintain balance on telephone wires high up the ground as well as in trees. Its function is similar to how a tightrope walker uses a pole to balance. They can also use their long tail, which is 40 percent of their body length, to protect their face and body from dogs, raptors, and other predators.

The blood vessels in the tail serve as an efficient thermoregulation system, opening blood circulation to the tail to cool the squirrel, and closing it to retain heat. Raising their tail over their body affords them the ability to enjoy the cool shade it provides. It also serves as a warm blanket that greatly helps to keep them warm during cold winter nights. Lastly, their tail is critical in communicating to other squirrels and potential predators.3

Their diet

Squirrels are herbivorous, subsisting on seeds and nuts, but some will eat insects and even very small vertebrates.2 They have large incisor teeth designed to crack open their diet of walnut, acorn, hickory and other nuts. Their constant gnawing helps them to keep their teeth razor sharp. Both tree and ground squirrels live in the same area year-round, including the cold winters. A motivation to write this paper is to understand how squirrels survive the ferocious winters where I live. Ground squirrels live on, or in the ground, and not in trees, and hibernate during the winter. Their heart rate and breathing rate slows down greatly and their body temperature falls below zero in preparation for hibernation.

In contrast, gray tree squirrels rely on sheltered nests made from twigs and leaves, or dens in trees like woodpeckers, to sleep. In the winter they sleep in their nest or den and rely on fat reserves, and stored food to survive the long, cold winters.3 Also, in preparing for winter, they maximize their food consumption and body mass. They venture out during the morning and evening only if their food supply is low. They prepare for the winter by storing acorns and other nuts, berries, and tree bark in shallow holes near the trees where their nest is located. Squirrels use spatial memory to locate stored food, and often bury their food near landmarks to aid them in remembering where they stored it.4

Evidence for squirrel evolution

Evolutionists believe that squirrels evolved about 36 million years ago from some hypothetical “more primitive rodent.”5 Previously, the earliest squirrel fossil evidence was found in western North America Darwin-dated to about 36 million years ago. A nearly complete skeleton was discovered in 1975 which “is surprisingly like that of a modern tree squirrel.”5 The skeleton of the find, determined to be a D. jeffersoni breed squirrel, was

“…discovered in early Oligocene deposits of Wyoming, [and] represents what may be the oldest fossil squirrel known… Except for minor differences in joint construction, the skeleton is strikingly similar to that of Sciurusniger, the living fox squirrel. It differs from extant ground squirrels in the more gracile proportions of its long bones and asymmetry of foot construction. This early member of the squirrel family was clearly an arboreal squirrel, with morphology, and presumably habits, very similar to those of extant Sciurinae.”6

The bones that were examined were judged to be “identical” to modern squirrels.6

The newest discovery after 1975 was a squirrel-like creature from China Darwin-dated over 200 million years old. The fossils were discovered by private collectors and amateur paleontologists in the fertile fossil province of Liaoning.7 The phylogeny [evolutionary relationship] of the fossils found “remains unsolved and has generated contentious views on the origin and earliest evolution of mammals.”8 As two of the leading experts of squirrels observed:

“biologists consider tree squirrels to be living fossils because they remain virtually indistinguishable from European and North American specimens that lived more than 5 million years ago.”2

Squirrels are only one of hundreds of examples of living fossils.9

Many examples of variations within the genesis kind exist, such as documented by Michael Steele and John Koprowski,2 but I have been unable to locate any evidence for the evolution of squirrels from a non-squirrel. In short, the origins concern is not of variations within the genesis kind, but the evolution of the first squirrel from a non-squirrel. From what is known, the first squirrel was very close to identical to modern squirrels. And if a local squirrel is making off with seed from your bird feeder, just reflect that they are all wonderful creations!

This is reprinted with permission from Creation Dialogue Volum 48, #2 and is by Jerry Bergman, the author of “Wonderful & Bizarre Life Forms in Creation.” For more on the wonder of squirrels, check out Mark Rober’s 20-minute video below. Though this is a secular presentation, it highlights God’s genius in crafting these incredibly clever creatures. Parents, cautions for the video include a couple uses of “fricken” and a reference to a squirrel stuffie dressed up in a bikini as a “homewrecker.” 

Endnotes

1 Rose, Nancy. 2014. The Secret Life of Squirrels. New York, NY: Little Brown.
2 Steele, Michael A., and John L. Koprowski. 2001. North American Tree Squirrels. Washington, D.C.: Smithsonian Institution Press.
3 Cheevers, Carrie. 2020. How do squirrels prepare for winter? Spectrum News, November 11. https://spectrumlocalnews.com/nys/central-ny/weather/2020/11/11/how-do-squirrels-prepare-for-winter-
4 Jacobs, Lucia, and Emily Liman, 1991. Grey squirrels remember the locations of buried nuts. Animal Behaviour. 41 (1): 103-110, January.
5 Thorington, Richard W., and Katie E. Ferrell. 2006. Squirrels: The Animal Answer Guide. Baltimore, MDJohns Hopkins University Press.
6 Emry, Robert, and Richard W. Thorington, Jr. 1982. Descriptive and comparative osteology of the oldest fossil squirrel. Protosciurus (Rodentia: Sciuridae). Washington, D.C. SMITHSONIAN INSTITUTION PRESS, Number 47.
7 Choi, Charles Q. 2014. Ancient squirrel-like creatures push back mammal evolution. Live Sciencehttps://www.livescience.com/47774-ancient-squirrels-push-back-mammal-evolution.html
8 Shundong, Bi, et al., 2014. Three new Jurassic euharamiyidan species reinforce early divergence of mammals. Nature. 514 (7524): 579-584, September 10; doi: 10.1038/nature13718. Epub.
9 Eldredge, ‎Niles, and S.M. Stanley. 2012. Living Fossils. New York NY: Springer-Verlag.

Other references

Pope, Joyce. 1992. Living Fossils (Curious Creatures): Animals Unchanged by Time. Austin, TX: Steck-Vaughn Library.
Emry, Robert, and Richard W. Thorington, Jr. 1984. The Tree Squirrel Sciurerus carolinensis  as a living Fossil. In: Eldridge, Niles, and S.M. Stanley. Living Fossils. New York, NY: Springer-Verlag.


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Book excerpts, Book Reviews, Science - Creation/Evolution

Giraffe: nature’s gentle giants

This is Chapter 7 from Dr. Jerry Bergman’s new book Wonderful and Bizarre Life Forms in Creation which you can order at Creation Science Association of Alberta. ***** Giraffes, the tallest living terrestrial animals on earth, are often called nature’s gentle giants due to their nonaggressive persona. Their most well-known trait is their long neck, longer than that of any living animal. Their 6-foot (1.8-meter) neck weighs about 600 pounds, more than the entire body of most animals. Their total height often reaches 20 feet and their weight 4,250 pounds. They are enormous animals. Their legs alone are taller than many humans, about 6 feet. They can run as fast as 35 miles per hour (mph) over short distances, or trot at 10 mph for longer distances. Giraffes are favorite animals in many cultures, both ancient and modern, and are often featured in books, paintings, and even cartoons. This is not only due to its long neck but also to its very distinctive coat patterns. It looks like the paint called “crackled” that shrinks as it dries, leaving distinct patterns of cracks spread throughout the animal’s body. For most young people, the giraffe is one of the most intriguing and exotic of all animals. It is so unusual, and in such contrast to other animals, that many people typically are more interested in it than many other fascinating creatures. In fact, the word “giraffe” is derived from the Arabic zerafa, a poetic variant of zarafa, meaning “lovely one” or “charming.”1 As one author noted, viewing a giraffe is one of humankind’s greatest visual experiences.2 The giraffe’s intelligent design The giraffe’s entire body – both its anatomy and physiology – is tightly intertwined as a single functional unit.3 The giraffe is an excellent example of intelligent design that demonstrates special creation. Its neck alone is a wonder of enormously complex design that requires all necessary parts to be in their proper places before its neck structure is functional. As Charles Darwin said, it is a beautiful animal with “an admirably coordinated structure” of many parts in its neck. Of interest, in The Origin of Species Darwin did not mention the giraffe’s neck as an example of evolution until the sixth edition, and then only in response to a critical review of his book by creationist St. George Mivart.4 In this work, it is clear that Darwin never regarded the giraffe’s long neck as central evidence of natural selection like biology textbooks that discuss evolution often imply today. Another major problem with the standard textbook story is that Darwin accepted Lamarckianism later in his life. Lamarckian theory of acquired characteristics explained giraffe neck evolution by arguing that constant stretching slowly elongated their necks, and they then passed on their beneficial longer neck trait to their offspring.5 Darwin resorted to the idea that evolution occurs by use and disuse of body parts because he was unable to come up with a plausible theory that explained the origin of genetic variety that Natural Selection could select.6 Darwin knew that without a viable source of genetic variety, no evolution can occur and his theory was dead. To produce a 6-foot-long neck from a short-necked animal (like evolution requires) necessitates hundreds or thousands of simultaneous, or nearly simultaneous, mutations – a set of events that has a probability of zero. It cannot just become longer, but requires a very different design than the less-than-one-foot neck that is common in most mammals. The late Harvard professor Stephen Jay Gould said, “the long neck must be associated with modifications in nearly every part of the body – long legs to accentuate the effect, and a variety of supporting structures (bones, muscles, and ligaments) to hold up the neck.”7 The giraffe’s head and neck are held up by large powerful muscles strengthened by nuchal ligaments anchored by long dorsal spines on the anterior thoracic vertebrae. The giraffe’s neck vertebrae use an atlas-axis joint that allows the animal to tilt its head vertically and reach more branches with its tongue to obtain food. Giraffes require not only long necks to reach tall trees, but also long legs and even long faces and tongues (their tongues are over a foot long) to reach the high growing acacia leaves they favor. One major problem for Darwinists is how natural selection simultaneously altered necks, legs, tongues, prehensile lips, knee joints, muscles, and complex nervous system and blood-flow control systems to control the pressure necessary to pump blood from the heart up to the giraffe’s distant brain. The common explanation of the giraffe’s long neck is that it was not produced by gradual evolution but instead mistakes called mutations produced it.8 To eat grass or drink water, because they are the tallest animals in the world, giraffes must move their heads to a point seven feet below their heart and, when upright, to a point about eleven feet above it. When the giraffe puts its neck down to drink, one would expect blood to rush into its head. Then when he raised his head after drinking, the blood flowing away from its head should cause it to faint. But a system of ingeniously designed reservoirs and valves inside its arteries prevents this from occurring. Its strong heart beats 150 times per minute. A spongy tissue mass below the brain helps to regulate blood flowing to the brain to ensure that rapid pressure changes are blunted.9 When water is available, giraffes drink regularly from ponds and streams. But during a drought, they can survive very well without water for several weeks at a time because they can satisfactorily obtain their needs from plants.10 Giraffes are an Icon of Evolution One of the more common icons almost universally presented as proof of evolution is giraffe evolution. It is used in high school and college biology, anthropology, and evolution texts. Science “has made giraffes the very symbol of evolutionary progress.”11 So important was this icon that Francis Hitching titled his critique of Darwinism “The Neck of the Giraffe” (1983). A survey of all major high school biology textbooks found “every single one – no exceptions – begins its chapter on evolution by first discussing Lamarck’s theory of the inheritance of acquired characters,” then presenting Darwin’s theory of natural selection as the correct alternative to Lamarck’s theory.12 As a result, the “classic textbook illustration of our preferences for Darwinian evolution... an entrenched and ubiquitous example based on an assumed weight of historical tradition that simply does not exist.”13 Thus, this example teaches evolution by use of “a false theory,” and thus is a false icon.14 A typical explanation for the evolution of the giraffe’s long neck is that some giraffes, purely by chance, were born with fortuitously slightly longer necks, and that this conferred upon them a selective advantage enabling them to reach higher branches in times of famine and drought, which greatly improved their chances of surviving and leaving offspring similarly endowed with longer necks. Such a process repeated over many generations would inevitably lead to the long neck of the modern giraffe.15 The giraffe’s neck is used to illustrate how natural selection gives more variety within a population. In any group of giraffes, there always exists variation in neck length, as is true of any trait. Consequently, the theory postulates when their food supply is adequate, the animals do quite well, but when food is inadequate, giraffes with longer necks have an advantage. They can feed off the higher branches. If this feeding advantage permits longer-necked giraffes to survive and reproduce even slightly more effectively than shorter-necked ones, the trait will be favored by natural selection. The giraffes with longer necks will be more likely to transmit their genetic material to future generations than will giraffes with shorter necks.16 The problem with this theory is that it is not just a matter of stretching the neck. Rather, giraffes require an entirely new design. WHAT IS LAMARCKIANISM? Larmarckism or Larmarckianism is a theory of evolution named after Jean-Baptiste Lamarck. He believed that characteristics that an animal organism acquired during its lifetime could be passed on to its offspring. It’s the idea that if a man started working out and getting huge muscles, his offspring would have bigger than normal muscles too, even without working out. It is also the idea that if a giraffe managed to stretch out its neck by reaching for those leaves on those tallest branches, its offspring would be born with longer necks. Long neck essential for its lifestyle The giraffes’ long necks are critical in allowing these long-legged animals to rise from a lying position. They use their neck to shift their weight, allowing them to stand on their long legs. It is also critical in climbing and running, which involve snake-like, slithery movements that propels their entire body forward. The long, thin giraffe neck provides a great deal of surface area, which is also important for effective body cooling. For this reason giraffes – in contrast to many other large mammals that live in warm temperate areas – can remain in the hot sun for long periods of time. Darwinists give reasons why giraffes evolved their long necks which include for mating, for defense, for thermoregulation, to facilitate their fast-forward travel (up to 30 mph), or for one of many other reasons, but it is a poor icon for their theory. They propose that the giraffes’ long necks evolved for all of these reasons – or none of them. As Gould concludes, “The giraffe’s neck cannot provide a proof for any adaptive scenario, Darwinian or otherwise.”17 The giraffe’s neck is far more useful as an example of the many problems with Darwinism. Common claims of giraffe neck evolution fail The typical textbook story is that giraffes evolved long necks to reach the leaves located “at the tops of acacia trees, thereby winning access to a steady source of food available to no other mammal.”18 Some question why the trees did not evolve to become taller to prevent the giraffes from consuming their leaves. Although now an icon for Lamarck’s mechanism of evolution, Lamarck presented no evidence for this interpretation but rather only “a few lines of speculation.”19 His reference to giraffes in his classic work consists of only one paragraph based on zero data.20 Lamarck also wrongly claimed that the animal’s forelegs evolved to become longer than its hind legs, indicating that Lamarck was not familiar with the literature on this animal.21 Why giraffes are used to support Darwinism A major reason that the giraffe example is used to support evolution is because it is an easy illustration of Darwinism by artwork or photographs.22 Virtually all textbooks picture giraffes eating from acacia trees, incorrectly implying that its leaves are the main staple of their diet. So “appealing is this hypothesis that students of giraffe behavior and evolutionary biologists alike accept it.”23 Although the tall acacia tree leaves may be a preferred food source, giraffes will graze on many other tree and bush types. Plentiful foliage exists at the lower-levels of the tree, and giraffes also commonly consume grass and low bushes and many kinds of ground-growing plants.24 Female giraffes are, on average, about a meter shorter in height than males – and they survive quite well. If leaves at higher levels are a large unexploited niche, then why have not many other animals, such as antelopes, also evolved the same long neck as giraffes have?25 One could argue that giraffes with shorter necks could thrive better because most of the foliage in the part of Africa where they live is near the ground, and it would be a decided survival advantage to be closer to the more plentiful ground vegetation compared to the comparatively rarer acacia tree leaves.26 All young giraffes feed on grass and bushes until their neck has grown long enough to reach the trees, usually at 3 to 4 years of age. The females spend over half their time feeding with their necks horizontal, indicating that their neck’s length may actually be a handicap. The giraffe diet is extremely varied. Generally, they are browsers, feeding by plucking leaves with their 17-inch tongue. Or they will grab a tree branch, put it into their mouth, and pull off leaves by twisting their heads. The over 100 plant species in the giraffe’s diet include flowers, vines, herbs, along with an occasional weaver-bird nest. If there are chicks in the nest, the giraffe eats them too, gaining some extra minerals from their bones. Giraffes also get minerals by gnawing on the bones of animals killed and left by hyenas and other predators.27 Other problems with the Darwinist textbook story One common theory is that the long neck evolved to aid in mating. The chief adaptive reason for evolving long necks could be sexual success “with a much-vaunted browsing of leaves as a distinctly secondary consequence.”28 The longer neck enables males to perform their ritual dominant battles called “necking.”29 The intrasexual competition theory assumes that “necking” behavior evolved first, then the neck length evolved due to sexual selection. Other evolutionists suggest that giraffes’ long necks evolved to function as look-out towers to spot potential predators. This, coupled with giraffe’s excellent vision, enables them to spot a lion as much as a mile away. The problem with this theory is giraffe’s have virtually no enemies – lions are the only wild animal that usually attacks them, but only when desperate.30 A lion is little match for a 2,000 to 4,000-pound giraffe. A giraffe hoof can kill a lion with a single blow. The giraffes’ best defense is not their necks, but it is their long legs and heavy hooves that are deadly to enemies. They defend themselves primarily by kicking. This theory may explain their long legs, but not why they evolved long necks. The legs could have evolved first to allow them to run from carnivores, then the neck grew so that the giraffe could stretch down to eat grass and drink water. The problem with this scenario is long legs do not always give the giraffe an advantage to outrun predators. Many of the fastest animals have legs far shorter than a modern giraffe’s. Fossil evidence for giraffe evolution lacking Much controversy exists about giraffe evolution, partly because no empirical evidence of giraffe evolution exists. Without any evidentiary constraints, scientists are free to speculate. As a result, they have tried to link giraffes to a variety of often very dissimilar animals.31 About a dozen giraffe (Giraffa camelopardalis) types are recognized. They are plentiful in the fossil record, and their bones have not changed much, if at all, in shape or size since giraffes first appeared in the record. The extant fossil record evidence leads to the conclusion that giraffes have been unchanged, by evolutionary reckoning, for about two million years.32 Furthermore, the fossil evidence that does exist “provides no insight into how the long-necked modern species arose.”33 Except that they are greatly elongated, the seven giraffe cervical vertebrae and leg bones are about the same number and are very similar to those of virtually all mammals.34 If giraffe neck and leg elongation occurred in evolution, then this should be obvious in the fossil bones. Yet no fossils supporting their neck evolution have ever been discovered. Savage and Long conclude that the origin of all three of the mainpecorans (giraffes, deer, and cattle) lineages “remains obscure” due to the total absence of relevant fossil evidence.35 Although some estimate that there exist approximately 50 extinct giraffe species, all are known from fossils extending back to the Miocene, estimated by evolutionists to be 17 million years ago. In spite of considerable effort, none of these show evidence for giraffe evolution. After unearthing millions of fossil bones, paleontologists have not located evidence for giraffe neck elongation, or any transitional stages. As Danowitz documents “the giraffe neck has been adequately researched” which has confirmed that “osteological demonstration of the fossils and evolutionary transformation of the neck is lacking.”36 Summary In conclusion, we agree with Gould that the standard giraffe evolution story “in fact, is both fatuous and unsupported,” and the existence “of maximal mammalian height for browsing acacia leaves does not prove that the neck evolved for such a function.”37 Gould’s major concern about this case is, “If we choose a weak and foolish speculation as a primary textbook illustration (falsely assuming that the tale possesses a weight of history and a sanction in evidence), then we are in for trouble – as critics properly nail the particular weakness, and then assume that the whole theory must be in danger if supporters choose such a fatuous case as a primary illustration.”38 We critics have nailed, not only this major weakness in Darwinism, but also its many other weaknesses and outright incorrect conclusions. This is Chapter 7 from Dr. Jerry Bergman’s “Wonderful and Bizarre Life Forms in Creation” Each of the 23 chapters examines a different animal or creature, so if you liked this, you can order the book at the Creation Science Association of Alberta. References 1 Allin, M. 1998. Zarafa: A Giraffe’s True Story, From Deep in Africa to the Heart of Paris. New York: Walker and Company, p. 5. 2 Burton, M. and R. Burton. 1969. Giraffe. The International Wildlife Encyclopedia, Volume 7. NY: Marshall Cavendish, p. 885. 3 Davis, P. and D. Kenyon. 1993. Of Pandas and People; The Central Question of Biological Origins. Dallas, TX: Haughton; Brantley, G. 1994. A Living Skyscraper. Discovery. 5: 26. April. 4 Spinage, C.A. 1968. The Book of the Giraffe. London: Collins. 5 See J. B. Lamarck’s English translation. 1914. Zoological Philosophy. Translated by Hugh Elliot. London, England: Macmillan, p. 122. 6 Gould, S. J. 1998. Leonardo’s Mountain of Clams and the Diet of Worms: Essays on Natural History. NY: Harmony Books, p. 312. 7 Gould, ref. 6, p. 309. 8 Sherr, L. 1997. Tall Blondes, A Book About Giraffes. Kansas City: Andrews McMeel, p. 40. 9 Hofland, L. 1996. Giraffes; animals that stand out in a crowd. Creation. 8 (4): 11-13.; Davis, P. and D. Kenyon, 1993. Of Pandas and People: The Central Question of Biological Origins. Dallas, TX: Haughton Pub. Co. 10 Peterson, D. 2013. Giraffe Reflections. Berkeley, CA: University of California; Dagg, A. 2014. Giraffe: Biology, Behaviour and Conservation. NY: Cambridge University Press. 11 Sherr, ref. 8, p. 40. 12 Gould, ref. 6, p. 302. 13 Gould, ref. 6, p. 302. 14 Gould, S. J. 1991. Bully for Brontosaurus. NY: Norton, p. 166. 15 Denton, M. 1986. Evolution: A Theory in Crisis. Bethesda, MD. Adler and Adler, pp. 42-43. Emphasis added. 16 Kottak, C. P. 2000. Anthropology: Exploration of Human Diversity. NY: McGraw-Hill, p. 166. 17 Gould, ref. 6, p. 317. Emphasis added. 18 Gould, ref. 6, p. 303. 19 Gould, ref. 14, p. 166. 20 Sherr, ref. 8, p. 41. 21 Gould, ref. 6, p. 306. 22 Hoagland, M., B. Dodson, J. Hauck. 2001. Exploring the Way Life Works: The Science of Biology. Sudbury, MA: Jones and Bartlett. 23 Simmons, R. E. and L. Scheepers. 1996. Winning by a neck: sexual selection in the evolution of giraffe. The American Naturalist. 148(5):771-786. p. 771. 24 Burton and Burton, ref. 2. 25 Gould, ref. 6. 26 Spinage, ref. 4. 27 Allen, T. 1997. Animals of Africa. Washington DC: Levin, p. 86. 28 Gould, ref. 6, pp. 317-318. 29 Sherr, ref. 8, p. 42. 30 Simmons and Scheepers, ref. 23. 31 Dagg, A. I. and J. Bristol Foster. 1976. The Giraffe: Its Biology, Behavior and Ecology. NY: Van Nostrand Reinhold. 32 Sherr, ref. 8, p. 42. 33 Gould, ref. 6, p. 315. 34 Gould, ref. 6, p. 309. 35 Savage, R. G. and M. R. Long. 1986. Mammal evolution. NY: Natural History Museum, p. 228. 36 Danowitz, M. et al. 2015. Fossil evidence and stages of elongation of the Giraffa camelopardalis neck. Royal Society Open Science 2: 150393. See also Danowitz, M., R. Domalski, N. Solounias. 2015. The cervical anatomy of Samotherium, an intermediate-necked giraffid. Royal Society Open Science. 2: 150521. 37 Gould, ref. 6, p. 318. 38 Gould, ref. 6, p. 314....


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