What about predators?

No matter where the transition is said to have taken place, any attempt to construct a theory about early human evolution must contend with, among other things, the problem of predation and how to avoid it (as much as possible). When dealing with the idea of the transition from hominoid to hominid on land, we can examine how our close relatives, chimpanzees for instance, deal with potential predators. They are similar in size and intelligence to our ancestors, and how they handle predators tells us something about how our earliest ancestors could handle predators on land.

When dealing with predation during a transitional period in the water, we also have to look at the problem squarely. The several variations of the Aquatic Ape Theory vary in whether the transition happened in salt or fresh water (although fresh water scenarios eliminate any possibility of explaining salt excretion as the salt water scenarios attempt to do), but they all agree that the transition to habitual bipedalism required a water environment. Except for Hardy's original claims, the amount of time actually spent in the water doesn't get discussed much, but we would have to assume that it must have been most of the time spent in locomotion, or we wouldn't expect bipedalism to be adopted for the reasons the AAT/H suggests. The reasons given are that if the hominids weren't bipedal, the water would be over their heads, and that the water would support the weight of the hominid, lessening strain. Both these requirements of the theory suggest that we're talking about spending many hours a day in water that is considerably more than waist deep. This makes for an enormous amount of exposure to common and vicious predators that would be seldom, if ever, encountered by a land-based transitional hominid (although they would be expected to occasionally get water from water holes, lakes, rivers, and streams, these land-based hominids might reasonably be expected to more often get their water the way chimpanzees in areas without standing water most often do, for instance by using leaves as a sponge).

Most AAT/H write-ups also make statements about the lure of this water environment for safety from predators. However, rather than being a haven from predators, this environment would not only expose such hominids to a great number of predators, but also predators which seem much harder to defend oneself from. To explain this, I'll give information about both sharks and crocodiles, which would be expected to be the main predators of such hominids, whether in salt or fresh water. Both crocodiles and sharks which are highly dangerous to humans even today are to be found in both fresh and salt water in Africa.

The bottom line on dealing with predators is that a species doesn't have to be able to avoid them completely, but in order for the species to survive, they have to avoid predators well enough to be able to replace their numbers. Some animals do this simply by having enormous numbers of young; even some mammals have large numbers of young. But humans and apes don't do this; in fact primates in general have relatively few young. To see if such an animal -- medium-sized and having relatively few young -- can survive predation in a given environment, we can look to see if any such animal actually has managed to do so. For a postulated land-based transition, we do see such an animal -- chimps. For a postulated aquatic-based transition, we see no such animal  of any species anywhere in the world.


First, do AAT/H proponents claim that an aquatic environment was safer than land?

Sir Alister Hardy, "Was there a Homo aquaticus?", article originally appeared in Zenith, 1977, vol. 15(1):4-6. Reprinted in 1982 The Aquatic Ape by Elaine Morgan, Stein and Day: Briarcliff Manor, N.Y.

pg. 150:
"So after some twenty million years or more of living a semi-aquatic life -- I must make it clear that I do not suppose man spent more than perhaps five or six hours in the water at a time -- Homo aquaticus left the sea (or lake) a very different creature from when he first entered it."

pg. 150:
"Perhaps it was not only a shortage of food that sent man to the water in the first place, but also a means of escaping from powerful predators: possibly Homo aquaticus was only able to survive and evolve with the help of a number of small sandy or rocky islands stretching up the tropical coasts or margins of lakes where he could live in large colonies, like those of seals or penguins, and where his only enemies were sharks and killer whales in the sea or crocodiles in lakes and rivers."


The following are from:
1991 The Aquatic Ape: Fact or Fiction? Edited by Machteld Roede, Jan Wind, John M. Patrick and Vernon Reynolds. Souvenir Press: London.

Leon P. Lumiere
Chapter 3. "The Evolution of Genus Homo: Where It Happened"

pg. 27:
"The dwindling forest would produce exactly the environmental conditions required by the Hardy hypothesis; those apes near the coast, losing their forest, gradually would be forced into water to find both food and protection from predators."


Derek Ellis
Chapter 4. "Is an Aquatic Ape Viable in Terms of Marine Ecology and Primate Behavior?"

pg. 37:
"How did apes survive on the savannah when there were fierce, fast predators there, day and night?"

pg. 67:
"Escape from land-based predators, when the apes were on shore, would be by running back to water and swimming away."


From these quotes you can see that escape from predators is considered to be an important part of the purported aquatic transitional environment. Note that even without considering aquatic predators, the idea of hominids escaping land-based predators such as lions by "running back to water and swimming away" is problematic, since large cats such as lions often hunt by water holes, streams, etc. and chase their prey into the water and kill them there. Since human swimming speed is much slower than human running speed, the usefulness of this method of escape seems to be an assumption that doesn't hold water. But here I am primarily concerned with describing the habitats and habits of water-based predators, to explain why they are such an intractable problem for the AAT/H, but not for theories of a land-based divergence.


Land-based predators

How chimpanzees react to predators

In reading what AAT/H proponents say -- both in published works and what they say online -- it seems they believe that our earliest hominid ancestors just couldn't have survived on land because of land-based predators. They also seem to feel (because that's what they say over and over) that the only option available to hominids on land is to climb trees or run away from predators. They would've realized they were wrong if they had done even the most basic of research into how our ape relatives handle the dangers of predators.

In fact, predation is not much of a problem overall for chimps, which might seem odd until you look at what you face when you face a chimp. What you face is usually not just a chimp, but a group of chimps. A group of strong, howling, stick and/or rock throwing gang of vicious little hominoids. They kill baboons and leopard cubs (with leopard-mommy present) with no more armament or natural ability than australopithecines had. They are not defenseless out there, and neither were australopithecines. In fact, even lone chimps have been seen sleeping overnight on the ground in areas frequented by leopards, which further suggests that they don't have much trouble with such predators.

What we see when we look at predation on chimpanzees, those animals so similar in size and intelligence to our early ancestors, is that they have more severe problems (ie. they get killed) with leopards in more heavily forested areas. In more open wooded savannah they show little concern with leopards. Perhaps Adrian Kortlandt's experiments during the 1960s would give us a clue as to why this is:

During the 1960s Dr. Kortlandt, a Dutch researcher, did a number of experiments with wild chimpanzees in natural populations in Africa. One of these was to see how different populations of chimps react to predators. To do this, he used a stuffed leopard dummy with electrically moveable head and tail. A baby chimpanzee doll was placed in the leopard's front paws and the dummy was placed where it would be encountered by mixed groups of chimpanzees, including females with young, in all the experiments. Several populations of chimpanzees were so tested several times, including groups in two different jungle areas, and a group of savannah woodland chimpanzees. All the chimp groups reacted by picking up sticks as clubs, breaking small trees and tree limbs to use as clubs, and throwing these at the leopard dummy. An interesting difference emerged between the jungle chimps and the savannah chimps. The jungle chimps, while aggressive toward the leopard, were uncoordinated in their attacks and when throwing objects, never actually hit the leopard.

Dr. Kortlandt observed:

"The results with savannah chimpanzees, however, were quite different. They grabbed the largest of the available clubs, which was 2.10 m long, and they tore down small trees of about the same length; they slashed viciously at the leopard with these. With the aid of the film we made, we could measure impact velocities of approximately 90 km/h, which would have been sufficient to break the back of a live leopard. In addition, there was teamwork in evidence during these attacks, again in contrast to what we observed in the jungle chimpanzees. During the final attack the dummy was encircled by five chimpanzees, while two others stood in readiness at some distance, in case they should be needed. Then the leader grabbed the tail of the leopard and ran away, tossing the predator so that the head flew from the body.

"With that, the enemy was considered 'dead'. The apes showed no more fear of it, and the youngsters were allowed to touch it. The attacks on its head, however, continued during the whole day.

"A side effect of the experiment was the observation that the savannah chimpanzees more often walked erect than do the jungle chimpanzees."

Kortland, A.; pp. 44-46, in Grzimek's Animal Life Encyclopedia vol 11: Mammal II Dr. Bernhard Grzimek, ed. Van Nostrand Reinhold: New York, Cincinnati, Toronto, London, Melbourne.

Perhaps this difference is the result of being able to see your potential predators, an great advantage over having them sneak up on you unawares.

Chimpanzees do not seem to be overly afraid of big cats; besides the cases of chimpanzees occasionally sleeping on the ground while in leopard country, there are other reports that show their reaction. Dr. Kortland did another test in the sixties with a stuffed leopard with a chimp doll in its paws; two female chimps threw sticks at it, apparently distressed at the plight of the "youngster". Bands of chimps have been spotted screaming at lions (from a distance) but holding their ground.

Then there was that leopard den. A band of chimps went over to a leopard den (sounds like "a gorilla walked into a bar..."; well, they really did; this took place at Mahale on October 3, 1984) and started screaming up a storm outside the den. This chimp group included not only adult males, but also females and young. From the sounds inside, the researchers observing this determined the mother leopard was inside at the time (but they didn't crawl in and check for some reason ;-). A couple of male chimps did, however, and dragged out one of the leopard's babies and beat it to death. During this period, some of the chimps were within 3 meters of the den's entrance, and this group included not only males, but several females, one with an infant.

So chimpanzees are not so afraid of large cats as we might reasonably suppose them to be. (That's understatement.) In fact, speaking about predation on chimps by large carnivores, Mariko Hiraiwa-Hasegawa et al. write:

"Most of the evidence is, however, only circumstantial and the predation pressure to the apes, if ever, seems to be extremely low. Moreover, chimpanzees have been observed to show 'offensive' rather than 'defensive' behavior toward such predators."

pg. 12, Hiraiwa-Hasegawa, Mariko; Richard W. Byrne, Hiroyuki Takasaki, and Jennifer M.E. Byrne, 1986, "Aggression toward Large Carnivores by Wild Chimpanzees of Mahale Mountains National Park, Tanzania", pp. 8-13, in Folia primatologica, volume 47.

Richard and Jennifer Byrne note:
"Researchers studying chimps have seen them encounter leopards a number of times. Sometimes, the chimps hardly react to the sight of a leopard, but usually they call aggressively and have managed to chase leopards away. In the daytime, leopards seem to be somewhat wary of the apes, even though, at up to 200 pounds, the cats are much larger than the primates, which weigh 70 to 85 pounds."

pg. 22, Byrne, Richard W.; and Jennifer M. Byrne, 1988, "Leopard Killers of Mahale", pp. 22-26, in Natural History, volume 3.



Aquatic Predators -- Crocodiles

The various AAT/H accounts make many statements about the lure of this water environment for safety from predators. My point is that rather than being a haven from predators, this environment would not only expose such hominids to a great number of predators, but also predators which seem much harder to defend oneself from.

Both crocodiles and sharks which are highly dangerous to humans even today are to be found in both fresh and salt water in Africa. And keep in mind that our transitional hominid ancestors were smaller than we are and also didn't have even such relatively "sophisticated" weapons as primitive hand-axes (ie., sharp-edged rocks).


The following quotes are from:
1989 Crocodiles and Alligators Various editors and contributors: Consulting Editor, Charles A. Ross (Museum Specialist, Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, D.C., USA) Facts on File: New York and Oxford.


My additional notes will be in bold face and brackets [], like this:

[question: how do we know there were crocodiles in eastern Africa at the time of the transition?]

"Evolution and Biology: Evolution". Chapter by Dr. Eric Buffetaut (Director of Research, Centre National de la Recherche Scientifique, University of Paris, France)

pp. 37-38:
The ancestry of the Nile Crocodile (Crocodylus niloticus) and, to some extent, of the African Slender-snouted Crocodile (Crocodylus cataphractus) is known with some precision because of abundant crocodile fossils from the Tertiary and Pleistocene of northern and eastern Africa.

[Okay, they were around (and had been for some millions of years), but would crocodiles be in the sorts of habitats that the purported aquatic hominids were in?]

"Behavior and Environment: Habitats". Chapter by Dr. Angel C. Alcala (Professor of Biology and Director, Marine Laboratory, Silliman University, Philippines) and Maria Teresa S. Dy-Liacco (Research Assistant, Marine Laboratory, Silliman University, Philippines)
 

pg. 136:
Crocodilians are amphibious vertebrates, spending part of their lives in water and part on dry land. They inhabit rivers, lakes, ponds, marshlands, swamplands, and estuaries.

pg. 137:
The edges of freshwater lakes and ponds, where the water is shallow, receive abundant sunlight and therefore abound in rooted and floating plants that in turn support a diverse fauna. These edges of lakes and ponds, or marshes, are favorite haunts of crocodilians, since they reply on both water and land for their activities. The still waters of the lakes and ponds offer crocodilians a habitat that is rich in food organisms.

The lower reaches of rivers, where the water is slow moving, relatively warm, more saline, and well-stocked with plant life, also provide adequate cover and a good supply of food for larger aquatic organisms, including crocodiles. Freshwater and mangrove swamps are often well developed in these lower reaches.


[Well, that about covers it; they were in every type of habitat that these small hominids have been said to possibly have been in.]


This quote is from a sci.anthropology.paleo newsgroup post by Elaine Morgan:

"On the matter of crocodiles .. Instead of all these hypothetical crocodiles, read what really happens when the extant tribesmen in the Danakil area need to cross a crocodile-infested river today. They wade across it, with their cattle. The apparent reason is that the river is swarming with tilapia fish. Your average croc will not go through the strenuous business of grabbing the leg of a large mammal and threshing and twisting around to tear it off, if he is full of tilapia and simply not hungry. (Source: Africa's Rift Valley, in the World's Wild Places series by Time/Life books)"
[my note: reading the above mentioned book one is immediately struck by Elaine Morgan's research style; it is in this case at least, I must say, somewhat lax. The passage doesn't mention cattle, but rather "camels and goats", and the fish are catfish, not tilapia.

But the question is not really whether or not Morgan gets her facts straight, or even whether author Collin Willock can actually spot "apparent fear or even watchfulness" from his perch in a helicopter flying overhead, but rather whether Nile Crocodiles are, as Morgan implies, merely peaceful fish eaters who wouldn't harm a small aquatic biped. Let's see what the experts say.]
 

"Evolution and Biology: Living Crocodilians". Chapter by Charles A. Ross (Museum Specialist, Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, D.C., USA) and Dr. William Ernest Magnusson (Research Scientist, Instituto Nacional de Pesquisas de Amazonia, Brazil)

pg. 67:
Nile Crocodile (Crocodylus niloticus

Habitat: Known to occupy a wide variety of freshwater habitats, this species also frequents coastal areas in West Africa, and in southern Africa one was spotted nearly 11 kilometers (7 miles) off the Zululand coast. From time to time crocodiles are washed out from East African river mouths to the sea; some of these have been able to cross to the island of Zanzibar [note: Zanzibar is 22 miles off the coast of Tanganyika, which together form the republic Tanzania] and crocodiles are occasionally found on beaches or river mouths in Kenya.

Distribution: The widespread crocodilian of the African continent, it is found throughout tropical and southern Africa, and Madagascar. its historical distribution included the Nile River delta and the Mediterranean coast from Tunisia to Syria. Isolated populations of the Nile Crocodile are known to have existed in lakes and waterholes in the interior of Mauritania, southeastern Algeria, and northeastern Chad in the Sahara Desert.

Diet: Very large animals eat antelope, zebra, warthogs, large domestic animals, and humans.


[I'm not suggesting that the aquatic hominids were romping about in Asia, and note only that the Indopacific Crocodile may have had a wider range at one time. The main reason I've listed info on them is that it gives a clear picture of the abilities of crocodiles to live even in oceanic waters, travel great distances, and colonize new areas. It has also been found that in areas where Indopacific Crocodiles do not live, such as when and where they were hunted out in the 1950s and 1960s, other crocodiles took over those habitats, including salt-water habitats.]

pg. 68:
Indopacific Crocodile (Crocodylus porosus)

Habitat: Commonly encountered in marine habitats, the common names Estuarine or Saltwater Crocodile are, however, misleading since this species is often found in freshwater habitats such as large rivers and lakes.

Distribution: The most widely distributed of all living crocodilians, the Indopacific Crocodile is found throughout the tropical regions of Asia and the Pacific, wherever there is suitable habitat. Its distribution is still not fully known but recent research suggests that it is found from the islands of the Indian Ocean, coastal India and Sri Lanka, through mainland Southeast Asia, the Indonesian and Philippine islands, northern Australia, New Guinea, as far as the Belau Islands and perhaps Fiji in the Pacific Ocean. The ability of this species to survive in the open ocean has enabled it to reach, and sometimes colonize, many small islands such as the Cocos Islands (nearly 1,000 kilometers from land) and the New Hebrides. Stories of these crocodiles out in the open ocean abound and some individuals have been seen with pelagic barnacles attached to their scales.

Diet: Large animals eat whatever they want, including a variety of mammals and some birds. Fish also form part of the diet.


[More on food and hunting styles of these crocodiles.]

"Behavior and Environment: Food and Feeding Habits". Chapter by A.C. (Tony) Pooley (Consultant on Crocodile Farming, Conservation, and Education, Scottburgh, South Africa)

pg. 83:
The Nile Crocodile has an extremely wide range of mammals in its diet ranging from cane rats to Cape buffaloes, which can be as heavy as itself. Mugger, Indopacific, and Nile crocodiles also include humans in their food range.

pg. 83
Crocodilians are usually regarded as idle hunters that lie in wait in the offshore shallows for the approach of unsuspecting prey. They rely on camouflage and an ability to lie submerged with only their nostrils, eyes, and ears above the surface to scent, see, and hear approaching prey. From this concealed position they can launch themselves out of the water with astonishing speed, and may make a rush of several meters up a beach to snap at prey approaching the shoreline. Even large crocodilians are capable of vaulting almost vertically out of the water to a height of more then 1.5 meters (5 feet) to snap at birds or animals on river banks above them.

pg. 86:
Sometimes the crocodile erupts from the water into the midst of a herd of drinking antelope then uses its massive bony head to deliver sledge-hammer side-to-side blows to stun prey, break limbs, or knock an antelope into the water.

pg. 86:
Many of the larger crocodilians are known to take advantage of the habitual behavior of their prey, taking up position in the water on regularly used game trails, or at well-used river crossings or watering sites for humans and livestock, particularly if previous attacks at these sites have been successful.

pg. 86 (picture of crocodile attacking a wildebeest, captioned):
On their long migrations vast herds of wildebeest have to cross many streams and rivers. With so many animals to choose from this crocodile does not even bother to submerge before attacking.

pg. 90:
In other Zululand rivers similar behavior may be seen in summer when rivers flood and water spills over into channels leading to natural pans. The crocodiles form a barrier where a channel enters the pan, facing the inrushing water and snapping up river fishes such as bream (genus Tilapia) and catfish.


[Okay, it's clear that crocodiles, and Nile Crocodiles in particular, are not the peaceful, fish eating, Disneyesque creatures Morgan suggested. But surely they aren't really capable of killing and eating humans! Keeping in mind that the humans of today, even those with the most primitive of weapons, are better armed than our earliest hominids.]

"Crocodilians and Humans: Attacks on Humans". Chapter by A.C. (Tony) Pooley (Consultant on Crocodile Farming, Conservation, and Education, Scottburgh, South Africa), Tommy C. Hines (Consultant on Alligator and Crocodile Management, Florida, USA), and John Shield (Veterinarian, Cairns, Australia)

pp. 173-174:
Adult Nile Crocodiles weighing as much as 1,000 kilograms (2,200 pounds) and up to 6.5 meters (21 feet) in length have been recorded. The Nile Crocodile has evolved on a continent where it has had to contend and compete with a far greater variety of competitors, as well as potential prey species, than any other crocodilian in the world. Competitors in the aquatic habitat include predatory fish and sharks, monitor lizards, three other crocodile species, and hippopotamuses. On land, it needs to defend territory, nest sites, and offspring against a range of predators and competitors ranging from small mongooses to elephants, and, of course, humans. Consequently, the Nile Crocodile is one of the most aggressive of all crocodiles. In order to survive in habitats populated by such a diverse fauna, it has become a versatile and opportunistic hunter, and master predator of the aquatic environment. 

[So it's good at its job, but what about defense? What about spotting it coming and getting out of the water?]]

pg. 177:
Crocodiles, like sharks, are rarely seen prior to an attack. The attack is swift, silent, and without warning.

pp. 175-176:
Like most crocodiles, when lying motionless in the water, the Nile Crocodile is cryptically colored and difficult to detect. It regularly enhances this natural concealment by lying next to a stand of reeds, under an overhanging tree, among water lilies, or drifting alongside a floating object.

It can breathe, smell, see, and hear while only the top of its nostrils and the top of its head are visible above the surface. From this sit-and-wait position it will make the final lunge at unsuspecting humans or antelope that approach the water's edge.

Alternatively, the crocodile may detect a potential victim when it is drifting some distance offshore. It will submerge and approach closer and closer, swimming underwater and bringing its head to the surface perhaps once or twice to check the location of the prey. The final lunge may carry the attacking crocodile several times its own length up the beach. Acceleration imparted by the powerful tail is combined with a simultaneous forward swing of the hind legs as the crocodile beaches. The toes and feet dig into the bank and the powerful legs lever the body upward. If the bank is steep, the crocodile appears to vault straight out of the water. If the prey is still out of reach, the hind-leg stride may be repeated and the crocodile may lower its head and hook it over the top of the bank to support its body for another stride. many an unsuspecting antelope or relaxed fisherman has been seized in this form of attack, even when 1.5 meters (5 feet) above the water.


[Okay, what about safety in numbers?]

pp. 176-177:
Contrary to popular belief, noise or safety in numbers does not deter a crocodile attack. Of the attacks investigated, only five of the victims were alone when seized. Several of the victims were snatched from amidst groups of men, women, and children who were either fording rivers, washing clothes or food, or bathing, and who were making a considerable amount of noise at the time. Field studies have shown that crocodiles are attracted from considerable distances to the sounds of a struggling animal in shallow water or to a shoal of leaping fish and that sound is often how prey is located.

Many witnesses and survivors of non-fatal attacks estimated that the crocodiles involved were in the range of 2.5 meters (8 feet) in length. These animals could be placed in the weight range of about 100 kilograms (220 pounds) and thus, weight for weight, the average human adult would stand a chance of escaping and surviving attack from a crocodile of this size. One could conjecture that these crocodiles were subadult or young adult animals. The injuries suffered by the survivors of these attacks also suggest that the crocodiles were small to medium-sized animals, for the wounds inflicted included the loss of hands, feet, and breasts, severe lacerations, and broken arms or legs.


A question from a newsgroup poster:
>>don't you think early man could have developed defensive
>>strategies to guard against crocodiles?"

[Okay, what about fighting it off?]

pp. 176-177 (continued):
However, the accounts of fatal attacks by large Nile Crocodiles -- 23 of the 43 attacks investigated -- indicate that these crocodiles were extremely aggressive and ferocious. There were several instances where crocodiles, having seized their victim, were either repeatedly stabbed with spears or knives, beaten with sticks, pelted with stones, or had sticks rammed down their gullets in order to prise the human victims from their jaws...but to no avail. In these attacks few bodies or remains were retrieved. Considering that a large Nile Crocodile may weight [sic] up to fourteen times that of an average human and can seize and drown Cape buffaloes as heavy as themselves, a human being, out of his or her element in the water, has little chance of surviving such an attack.
[The best defense seems to be not getting into trouble in the first place.]


[Now these are some accounts of the problem of crocodile predation on humans today. First note that this doesn't tell us anything about how likely it was to get attacked or killed millions of years ago, with numerous crocodiles and our ancestors being smaller and less well armed than we are now; what it does tell us is that, even with crocodile numbers being cut back due to habitat destruction and hunting, there is still a problem with these animals attacking and killing humans. (Estimates are that between 100-300 are killed each year in Africa by Nile Crocodiles and up to 1000 people a year throughout the range of the Indopacific Crocodile.)]

pp. 182-183:
Throughout the archipelagoes of Indonesia, the Philippines, and New Guinea, together with the adjacent land masses of Malaya and northern Australia, there is evidence that crocodiles have always exacted a terrible tool on villagers living close to the water. Only the problems of contact with isolated communities and poor communications have obscured the statistics on fatalities and when and how they occurred. Where reliable sources of information are available, they paint a picture of regular predation by crocodiles on villagers and even situations where entire communities have been terrorized.

A missionary at a village in northern Irian Jaya reported that no fewer than 62 of the villagers had been killed or maimed by a rogue crocodile in the 1960s. Six fatal attacks, and a great number of non-fatal attacks, occurred on Sarawak's Lupar River between 1975 and 1984. Tiny Siargo Island, off Mindanao in the Philippines, has reported the deaths of nine villagers in recent years, all possible victims of the same crocodile.

A fellow who lives part-time on Siargo emailed me and insisted I delete this account of the attacks on Siargo Island. Now I have nothing against deleting any info here that's wrong, but I didn't delete anything after his request. He just didn't provide any backup for his claim that these attacks never happened, and I found his claim unconvincing, especially compared to a renowned crocodile expert. First, he complained about Tony Pooley referring to Siargo as "tiny", and while I don't know as I'd describe it that way myself, I pointed out that it's far tinier than the island where I live. And if you lived on a "non-tiny" island how could you be so sure you'd heard all incidents of animal attacks? (I know I was surprised to learn how many cougar attacks had taken place on my island -- one of the world's hot spots for cougar attacks -- and even more surprised that a cougar had been found wandering about less than a mile from my apartment -- in the city -- only a few years before we moved here.) But the real problem is that he offered no evidence whatever, when it should've been fairly easy to do so, and hasn't -- despite requests -- for going on 6 years now. Please, if you want to have me change something you don't like, provide me with some evidence that you have a valid point.
As the Indopacific Crocodile grows, the mammalian component of its diet grows in proportion. An individual of 5 meters (16 feet) in length would generally be quite accustomed to killing pigs and, occasionally, cattle, buffaloes, and horses. There are reliable accounts of leopards being killed. Except where it has been hunted, there is no reason to believe such an animal would recognize a human entering its territory as anything other than a potential meal.

pg. 183:
When a potential meal approaches, in the form of a bird or perhaps a dog, a hungry crocodile, apparently asleep on the bank, may slip quickly and silently into the water. By the time the "meal" arrives on the scene there is no sign of danger but the crocodile is watching quietly from under the water. If the intruder approaches closely enough, the crocodile explodes into action and grabs it in a ferocious rush that has been compared to the eruption of a Polaris missile from its underwater base. The crocodile seizes the prey animal with its jaws locked onto the head, muzzle, leg, or whatever part of the body is within reach. If the impact of this first contact is not sufficient to disable the prey animal, the crocodile tries to drag it into deeper water. The notorious "death roll" may be used at this stage to unbalance the unfortunate victim. Once the contest has moved into the water, the advantages are with the crocodile and the victim is drowned or killed by crushing bites.

pg. 186 (picture of a river landing, captioned):
Adult Indopacific Crocodiles are territorial and will defend their territory against intrusion, even by boats. A local woman, only ankle-deep in the water beside this landing stage on the Daintree River, Australia, was taken by a large male crocodile in December 1985.

[This was a typical attack; neither the victim or either of the two men standing beside her heard or saw anything until she was grabbed and flipped off her feet too quickly to even make a sound.]


Lastly, a newsgroup poster made this suggestion:
>>These eggs would make a very good meal for early hominids and it would 
>>be an effective way to control the population of crocodiles as a whole.

[Now, since crocodiles undergo a lot of predation on eggs (and young as well), yet didn't decline in numbers until massive habitat destruction and hunting began a few hundred years ago, this doesn't make sense. Crocodiles have evolved to withstand massive losses of young -- about 90% or more.]

Behavior and Environment: Mortality and Predators Chapter by A.C. (Tony) Pooley (Consultant on Crocodile Farming, Conservation, and Education, Scottburgh, South Africa) and Charles A. Ross (Museum Specialist, Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, D.C., USA)

pg. 92:
During the first six months, and up to several years of life, hatchling and juvenile mortality from predators is high. In fact several African and Pacific crocodile management programs justify harvest of eggs and/or juveniles as recruitment of this segment of the population into the adult breeding population is so low. Some wildlife management specialists estimate a death rate as high as 90 percent during the first year of life. However, as a crocodile successfully runs the gamut of early life predators and reaches adulthood, the number of predators and the causes of mortality diminish rapidly. An adult crocodile has little to fear but its peers and humans.

pg. 95:
In Africa, the Nile Crocodile (Crocodylus niloticus) nest predators have been described from various countries and habitats. These include water and white-tailed mongooses, honey badgers or ratels, olive and chamca baboons, otters, warthogs, bushpigs, and spotted hyenas. Avian predators of nests include the Marabou Stork, which has learned to probe through the sand with its stout bill to remove eggs from unattended crocodile nests. However, the Nile or water monitor lizard is undoubtedly the major predator of crocodile eggs throughout the African continent and, over some nesting seasons, these lizards may be responsible for stealing up to 50 percent or more of all eggs laid.


Aquatic Predators -- Sharks

Both crocodiles and sharks which are highly dangerous to humans even today are to be found in both fresh and salt water in Africa.

This section describes the habitats and habits of sharks.

I must say, after reading about both sharks and crocodiles, that I feel that predation by crocodiles would have been a greater problem for the AAT/H's water-based transitional hominids than predation by sharks. There are three main reasons for this: first is that sharks, while they do often come into quite shallow water, are more common in greater depths of water. Second is that sharks seem to attack humans only partly for food; partly it's out of an apparent defense of what it considers its territory. Third is that attacks may only consist of one or two bites; but of course leaving a hominid crippled might well be essentially the same as killing it outright.

In contrast, crocodiles like to live in shoreside waters just where the AAT/H-proposed hominids are postulated to have lived; crocodiles generally stalk and kill mammals, including humans, as food; and crocodiles, once they get hold of their victim, do not let go, even when being pelted with rocks, stabbed with knives and spears, or when sticks are rammed down their throats. Crocodiles are serious about their job.

The information quoted here regarding shark attack comes from chapters about shark attack in many areas of the world, including the US, Australia, and South Africa. This information is applicable to all tropical and sub-tropical areas in Africa (the area in question here) as all three of the species of sharks which swim into and/or frequent shallow waters (and which are consequently most dangerous to humans) live in those tropical and sub-tropical African waters, as well as being widespread throughout the world.


Again, my additional notes will be in boldface and brackets []. [Like this.]

The following quoted material is from:
1989 Sharks in Question: The Smithsonian Answer Book Springer, Victor G. (curator in the Department of Vertebrate Zoology, Division of Fishes, National Museum of Natural History, Washington, D.C.), and Joy P. Gold (Technical Information Specialist at the Department of Vertebrate Zoology, National Museum of Natural History, Washington, D.C.) Smithsonian Institution Press: Washington, D.C. and London.

[Some people say crocodiles don't live in salt water; we've already seen that is wrong. Some also say that sharks don't live in fresh water; that is wrong as well. In fact, one of the most dangerous of sharks (the Bull Shark, sometimes also called the Zambezi Shark) lives in both fresh and salt water.]

pp. 66-67:
Icthyologists (scientists who study fishes) have been interested in the sharks that occur in freshwater. Formerly, sharks found in Lake Nicaragua, Lake Izabel in Guatemala, the Ogowe River in western Africa, the Zambezi River in eastern Africa, the Tigris River near Baghdad, and the Amazon River of South America, to name but a few, were each believed to be a different species that was confined to freshwater. Recent studies, however, demonstrate that in all these rivers and lakes there is but one species: the bull shark, Carcharhinus leucas, which is also commonly found in the warm, shallow waters of the oceans. In Lake Nicaragua, which drains into the Caribbean Sea by the broad Rio San Juan, the bull shark apparently moves freely between saltwater and freshwater. Even the rapids along the river seem to present no barrier to its passage. The bull shark has been implicated frequently in shark attacks on bathers, especially in warm freshwaters such as Lake Nicaragua and the Zambezi River, which have access to the sea.

[Is this shark dangerous to humans?]

pp. 116-117:
Bull Shark
Of all the sharks swimming the continental coasts of tropical and subtropical seas, the bull shark, Carcharhinus leucas, may be the most dangerous. In number of attacks on humans, it is one of the three species of sharks most often implicated. It may not have the white shark's reputation, but its large, heavy body, huge jaws, and very large teeth make it meter for meter just as formidable. Even though it appears to move slowly when cruising the shallows inshore, it is capable of fast, agile movements when it wants to attack prey. In Natal, South Africa, the bull shark is particularly notorious as an aggressive species, and it is caught four times more frequently than either the white or tiger sharks in the protective antishark nets set off the beaches.

pg. 117:
The species is relatively large, purportedly growing to a length of 3.4 m, but with an actual record of only 3.2 m (based on a report from Brazil). Individuals over 3 m are rare.

pg. 160 (from Appendix Three: Lengths of Selected Sharks):
Bull Shark (Carcharhinus leucas)
at maturity: male 1.57-2.26 meters; female 1.8-2.3 meters;
maximum total length: recorded 3.2 meters, reported 3.4 meters.
smallest free-living 0.56-0.81 meters

pg. 117:
The bull is the only shark known to live in the saltwaters of the oceans, the brackish water of estuaries and river mouths, and the far upper reaches of freshwater rivers and lakes. Even its newborn young and juveniles enter freshwater without difficulty. It travels from the Caribbean 100 km up the Rio San Juan to Lake Nicaragua, where it was long thought to represent a different land-locked, endemic species. It has also been reported from Lake Ysabel in Guatemala, the Mississippi and Atchafalya rivers in the southern United States, 3,700 km up the Amazon to Peru, the Gambia River on the middle upper west African coast, more than 550 km from the sea up the Zambezi River on the middle lower east African coast, the Tigris River of Iraq, the Hooghly River of northeastern India, and Lake Jamoer in New Guinea. These are but a few of the bodies of freshwater frequented by bull sharks. As recently as August 12, 1985, a large, 2.7 m bull shark weighing about 216 kg was caught in the Chesapeake Bay along the western North Atlantic seaboard.


[So they're fairly big, and they live virtually everywhere. What do they eat?]

pg. 118:
Bull sharks feed on a variety of prey and are almost as omnivorous as the tiger shark, the ocean's junk food eater; however, the bull is less likely to eat indigestible garbage. It favors bony fishes and other sharks, particularly young ones in the nursery grounds. In the sea, it will also kill and eat dolphins and sea turtles. In rivers, it has been known to kill hippopotamuses. Even the remains of large land animals, including antelope, cattle, dogs, and humans have been found among its stomach contents.

Dr. Leonard Compagno, who was the ichthyological consultant to the film Jaws, believes that the bull shark is quite possibly the most dangerous of all sharks, and that many attacks attributed to other species may actually have been committed by bull sharks. The famous, closely spaced series of five attacks -- four fatal -- that occurred in New Jersey in 1916, have been attributed to the white shark. At least three of the attacks, however, occurred two miles up a narrow tidal creek, a habitat type in which no white shark has ever been confirmed to occur. A tidal creek is a likely place for bull sharks to be found, and few other species of sharks have been reported from such a habitat. No other western Atlantic shark species is known to enter tidal creeks.


[They're big, they live virtually everywhere, and they attack and kill humans even today. They're one of the main reasons South Africa and Australia have erected expensive anti-shark nets on their beaches.]

pg. 108:
How does the white shark attack its prey? Generally by surprise, and from behind and below, sometimes in an accelerated headlong rush at 17 kph to 25 kph, sometime inverting on its back or rolling to its side, according to the size and posture of its prey.

The following quoted material is from: 1987 Sharks. Various editors and contributors: Consulting Editor, Dr. John D. Stevens (Senior Research Scientist, Division of Fisheries, CSIRO Marine Laboratories, Hobart, Tasmania, Australia) Facts on File: New York and Oxford.

[The following covers much the same ground, and simply confirms that the three species of sharks in question, the bull shark, the tiger shark, and the great white shark, are all dangerous to any animal which habitually uses shallow waters of seas. This especially holds true for the bull shark, which is highly dangerous to any animal which uses the waters of not only seas, but also estuaries, and rivers and lakes with an outlet to the sea. In other words, the habitat of the aquatic ancestor postulated by the AAT/H.]

"Shark Attack in Australian Waters". Chapter by Roland Hughes BSc (former editor, Australian Natural History, Sydney, New South Wales, Australia)

pg. 110:
Coppleson concluded that the swimmer attacked by a shark is usually either a lone bather, part of a small group or on the edge of a large group. Shark attacks can occur in all kinds of weather, on dull days and fine days, at high, medium or low tides, in clear, muddy or even brackish water.

pg. 116-117:
Bull or Zambezi Shark
Carcharhinus leucas
Because it is less physically impressive than either great white or tiger sharks, the bull shark's reputation as a danger to humans has been underemphasized. However, it is abundant in tropical and subtropical seas, estuaries and even freshwater rivers (specimens have been collected 3700 kilometers from the sea in the Peruvian Amazon). It frequents shallow water near beaches, and is a versatile and opportunistic feeder that will attack without provocation. The bull shark is a stout to heavy-bodied species that grows to 3.4 metres in length, and is now known to be the culprit in attacks formerly blamed on the elusive Ganges Shark (Glyphis gangeticus).

Tiger Shark
Galeocerdo cuvier
Regarded as the most dangerous shark in tropical waters, the tiger shares with the great white and bull sharks membership of the 'unholy trinity' of proven maneaters. It grows to about 6 metres and is responsible for repeated attacks on swimmers, divers, and boats.

Great White Shark
Carcharondon carcharias
Primarily a coastal and offshore species of continental and insular shelves, the great white grows to about 6 metres and is regarded as second only to the orca, or killer whale, as a marine predator. It has been identified in attacks on humans off California, southern Australia, New Zealand and South Africa.

"Shark Attack in the United States". Chapter by Dr. Guido Dingerkus (Director, Natural History Consultants, Goshen, New York, USA)
pg. 123:
One of the most dangerous sharks, and in tropical waters unquestionably the most dangerous, is the tiger shark (Galeocerdo cuvier).

pg. 123:
Off Bimini, in the Bahamas, the author has caught six of these sharks, ranging in length from four to six metres, in only one or two metres of water. It is, therefore, a species that poses a serious threat to bathers in shallow, warm waters.

pg. 124:
The bull shark, Carcharhinus leucas, is probably the next most dangerous shark in warm waters.

pg. 124:
Coming into shallow water, it will feed on almost anything it encounters, swallowing smaller prey whole and using its razor-sharp teeth to bite circular chunks out of larger prey. It is probably the only species to enter pure fresh water, and has been caught as far as 3200 kilometers upstream in the Amazon River. It is especially aggressive in fresh water, where it apparently comes to feed. In Lake Nicaragua many human deaths have been caused by this shark.

All these factors probably mean that the bull shark comes into close association with humans quite frequently.

"Shark Attack in South Africa". Chapter by Dr. Leonard J.V. Campagno (Senior Research Scientist, J.L.B. Smith Institute of Ichthyology, Grahamstown, South Africa)
pg. 137:
At least some writers have thought the Zambezi shark the most dangerous species in the warm waters of Natal, and responsible for many attacks off bathing beaches there. In terms of relative abundance and habitat the Zambezi shark is, or was, more likely to come in contact with humans than the tiger or great white sharks, which also occur in the warm inshore waters of Natal. Although smaller than the other two, the Zambezi shark has very large teeth, massive jaw muscles for its size, eats almost as wide a range of food as the tiger shark, and occurs in a greater variety of inshore habitats than the other species.
"Shark Attack in New Zealand". Chapter by Larry J. Paul BSc (Hons.) (Fisheries Research Division, Ministry of Agriculture and Fisheries, Adelaide, South Australia)
pg. 152:
How does one avoid becoming a shark statistic? Only by never going into the water, for sharks are unpredictable and no measures give total security.
[Although sharks may not have been quite as much a danger as crocodiles for a relatively small, comparatively slow swimming and defenseless aquatic ancestor, the AAT/H needs to address the extremely serious threat to these habitually aquatic creatures posed by both sharks and crocodiles.]