Tag: Wildebeest

Glacial Formation and Plate Tectonics Influence Species Survival in Africa – Part 1

Part I – Tectonics, Glaciers and Time

A few zebras and wildebeests grazing in the desert of the Ngorongoro Crater of Tanzania, with two safari vehicles in the background kicking up dust.
Fig. 3 Ngorongoro Crater in Tanzania, 2025 desertification

Introduction

The terrestrial forces of tectonic plate movement, ice ages and volcanic activity, together have changed the earth like no other forces except collision with extraterrestrial bodies. Southeast Africa has strategically benefited from these earth changing forces. This can be seen in the generation of a widely varied collection of mega and micro fauna and flora like no other place.

A panoramic view of a vast green landscape with patches of water, hills in the background, and a clear blue sky.
Fig. 10 The Ngorongoro 5 years ago.

The introduction picture shows a 7 zebras and 5 wildebeest in the Ngorongoro Crater. We went there using safari vehicles in 8/2025. The only road was made of irregular stones, ruts and dirt. Driving was difficult. Visibility was obscured for hours by dust as we drove across the crater. It is the caldera of the worlds largest above water volcano that was active 2.5 million years ago. It was famous for its wildlife. The image shows the greatest concentration of animals which we encountered along the way. To say that it was disappointing is an understatement. Fig. 10 comes from a posting on the internet.

Changing forces

Today we can see that the forces are changing. Tectonic plate is the slowest acting force acting in the level of hundreds of millions of years. And yet its rate and direction of movement can change dramatically in regions. This may be caused because glaciers and ice shelves are reduced. Glacialization operates at more rapid rate than plate movement with an effective speed measured in thousands of years. As the ice melts the weight of the water is more evenly distributed to the oceans thus altering the plate movement location and location of volcanic activity. Notably, the rate of vulcanism is unchanged. Volcanic ash, carbon dioxide and sulphur and gases are insignificant when compared to human activity. Anthropogenic CO2 emission for 2010 is estimated to be about 80 to 270 times larger than the respective maximum and minimum annual global volcanic CO2 emission. The results of action and reaction of human intervention parallel a cause and effect interference with historic geologic cyclical behavior. This may be the root cause of two possible effects of biological changes which are currently occurring. Survival of existing species is in decline. Generation of new species has slowed. This series of postings uses a contrast of two cat species, lions and cheetahs in Southeast Africa. Study of these species is intended to form a foundation for understanding how the change in the forces drive the current ecological conditions.

These four blogs are the result of thoughts and interpretations based on our latest safari to Africa that included Kenya and Tanzania. This was not a high-end trip. Instead it was a road trip to some of the lesser visited sights and it was during a period that was unexpectedly dry. I was particularly interested in the survivability of two well recognized cat species. The lions and cheetahs are two very different genus of predatory cat species at the apex of the food chain.

VOCABULARY

The vocabulary in these post also include several technical terms that apply to our discussion. For definitions, follow their links. Genetic drift, founder effect, gradualism, saltation, adaptive introgression and hybridization.

A close-up of a cheetah licking its lips with a blurred grassy background.
Fig 1. A distinction of genus is the outstanding characteristic to be followed in this series. Cheetah are from the genus Acinonyx while Lions are of the genus Panthera. They are not genetically related.

Let’s look at the driving forces and their results. The following charts show the approximate location of the Great Rift Valley region in Southeast Africa. This is a massive geologic event which is actively happening as we watch. The continent is splitting the eastern quarter of the continent off the main body. This gigantic split has created a huge valley that will someday be filled with ocean. It is accompanied by volcanoes, earthquakes, lava flows and uplifting plateaus.

GLACIAL REBOUND

From the last two glacial periods, 21,000 and 13,000 years ago, the continents are still recovering. The ice pack at the poles still hold the last remnants of that ice age. One result of this diminishing ice can be seen in the African desertification. The Sahara and Kalahari deserts are the result of the last ice age. When the poles melt and the Rift Valley floods the main portion of the African continent will recover. The deserts will bloom and the chronic drought in Africa will be concluded. The new continent will be created east of the Rift Valley. Migration may reverse. It just takes time. Never-the-less, the adaptable survivors will prevail.

Vast desert landscape featuring a rocky outcrop with vegetation atop, surrounded by dry, arid terrain and distant hills.
Fig.2 Olduvai Gorge in Tanzania, the Louis Leakey campsite, desert landscape

ECOLOGIC BARRIERS

As a result of the climatic changes, geographic barriers emerged. These are called Walls and they divide Africa into three eco regions.

These include the Saharan desert, the sub Sahil West-Africa separated from the Sahara by the line called the wall called the Sahil and East-Africa with Great Rift Valley, Fig.4, separated from wast Africa by the Great Wall of mountains.

The Great Walls of Africa limit the direction of animal migration and isolate the wildlife. This isolation has a double effect on all life forms by promoting speciation but also risking the compromises of genetic drift. In Fig. 5 the Sahil, shown as a green line, is the wall created by the Sahara. The Great Wall of mountains shown as blue line of Fig.5 parallels the Great Rift valley. Note that the regions of Kenya and Tanzania, Fig. 6 outlined in blue, are in high arid, desert risk locales.

MIGRATION

Through the two Great Walls there are narrow gaps called “bottle necks” . These geographic locations limit commingling and migration of species. These are the few areas through which animals can migrate. Except for the Nile river flowing through the Great Rift valley none of these areas follow the seasonal north-south wet weather patterns nor a river flow to another land mass. The access to Eurasia from the generative basis of Africa is through the three bottle necks of the Straights of Gibraltar, the Nile river delta and the Straight of Bab Al Mandeb. During the last 12,000 years the shallow Nile river delta crossing has been the least treacherous.

Mov. 1 Wildebeest migrating northward following the water and new grass. Lions, Cheetah and other predators follow the prey.

The illustration Fig. 7 is a conceptualization of the most direct routes for migration. Interestingly the Great Migration for animals from Africa also follows the projected route for hominoid migration. Mov.1.

Map of the Great Rift Valley and its geological features, including the Eastern Rift, Western Rift, and surrounding plates in East Africa.
Fig. 4 Location of the Great Rift Valley shown as the purple area in the red bracket. The insert shows the tectonic plats promoting the rift.
Map of Africa with highlighted Nile River, showing elevation variations in the southern region.
Fig. 5 The Great Wall of mountains and volcanoes west of the Rift are marked in the blue bracket. The Sahil marked in green, is the sub Saharan line south of the desert. The Great Wall and the Sahil are Africa’s migration barriers.
Map of Africa showing different risk levels for a specific factor, with regions colored in green, yellow, orange, red, and gray, indicating low to very high risk.
Fig. 6 Sub Sahil desertification is below the Sahara and is a high risk for drought. The light blue outline defines the Great Migration area. This area is at moderate drought risk.

The illustrated route could be followed in both directions as driven by climate change and the paths of migration of predated species sought after by the apex predators. As the glaciation advanced or retreated these routes would have water which would support grasses, insects, herbivores and carnivores. The Nile is the only north /south river. It flows to the Mediterranean through the Great Rift valley. Following the Valley waterway this leads to the choke points to the Eurasian continents. Following the east west routes of the Congo River, the Niger River or the Zambezi River leads to migration potential but dead ends at the two vast oceans.

Map of Africa showing various river basins highlighted in different colors, with a prominent pink line indicating a geographical feature.
Fig. 7 This is a conceptualized path for the bidirectional migration routes shown in red overlying a map of Africa.

We will follow two cat species which are the result of adaptations after the last Glaciation period. Panthera contains the largest number and variety of living members of the cat family. There are five living species: the jaguar, leopard, lion, snow leopard and tiger. It contains the five living species of “big cats” capable of roaring. Cheetahs belong to a completely different biological genus (Acinonyx).  They cannot roar, have distinctly different anatomy, including semi-retractable claws for high-speed traction and a unique, lightweight skeleton

A collage depicting six types of lions with labeled names: Transvaal Lion, Congo Lion, West African Lion, Nubian Lion, Southwest African Lion, and Asiatic Lion.
Fig. 8 Gross view of lion subspecies
An infographic displaying the four living cheetah subspecies: Southern African cheetah, Northeast African cheetah, Saharan cheetah, and Asiatic cheetah, along with their scientific names, distribution areas, and conservation statuses.
Fig. 9 Gross overview of cheetah subspecies

Continue to follow this amazing story of Earth changing forces. See the combination of struggle, adaptation and survival of life that sweeps across the planet through hundreds of thousands of years. Learn about the unique capabilities and risks to the Cheetah and the Lions. Because we are part of this great drama, you may use this knowledge to anticipate our future.

All photographs created by John Knapp

References:

Mitogenomic analysis of the genus Panthera

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#glacers, #tectonic, #migration, #Africa, #Nile, #walls, #barriers, #corridors, #cheetah, #lion, #genetic drift, #founder effect, #Ngorongoro, # Olduvai, #cats #wildebeest,

The African Great Migration and Its Significance

The last few days of our expedition gave meaning to our adventure. We were in the Kenyan Maasai Mara, thrilled by the larges animal migration of on Earth.

On the cover photo is a group of blue Wildebeest. AKA the common wildebeest Connochaetes taurinus) it is a large antelope found in Kenya and Tanzania.

One wildebeest is not photogenic. There is never just one. Tens of thousands of them live and move together as one massive organism. Hundreds of thousands of mixed species of animals move with them and between each other during the great wildebeest migration.
Migration map We were in the Maasai Mara during the last four days of August.

The Maasai Mara of Kenya is contiguous with the planes of the Serengeti National Park and the Tanzanian National Park. All are part of the Serengeti plane. These images are from the Kenyan Maasai Mara National Reserve. It was the most favorable point to observe the Great Migration when we were there. As the weather changes from dry to the rainy season the grass regrows. It is the grass which provides food for the grazing animals. This is irresistible to the wildebeest, zebra, impala, buffalo and other animals who follow this growth by the millions. The dead grass remains after the tops have been eaten to the ground or burned off. The rain brings a fresh regrowth. This regrowth replaces the razor-sharp stubble with soft young plants.

One of the most thrilling wildlife spectacles on earth was spread before us like pepper on a salad. We stopped to watch this ancient migration sight that this area supports. You can see in every direction that the savanna is covered by hundreds of thousands of animals. It is hard to comprehend that they actually number in the millions. They are visible to every horizon, slowly moving to follow the fresh growth. They meander about eating and mingling, occasionally fighting and challenging one another for mating or protecting one another from the daily challenges of survival, reproduction, and predation. For reasons unknown to us they may gallop along following some instinct or stamped when startled or frightened. It is this cumulative picture of integrated behavior based on soil, seasonal weather, prolific plant life and a massive accumulation of thousands of animal species which underscores the interdependency of this huge ecosystem.

Migrating animals wandering from one side of the horizon to the other. View of the north.

We did cross the Mara river and its tributaries where crocodiles and hippopotamuses were swimming or simply resting. The hungry crocodiles were ready at a wildebeest crossing to take advantage of the weakest or most vulnerable animals. We did not see this classical behavior but none-the-less the trap was set. Predators and scavenger animals follow this migration in the ladder of primacy with the lion at the apex.

The Mara river teeming with crocodiles waiting for the stampede.
The blue wildebeest, keystone animal of the Serengeti, Maasai Mara. Running with the group on its way into the future.

The wildebeest is the keystone animal of this ecosystem. It is the primary consumer of the grasses. It has a high reproductive rate. It is the resource upon which all of the carnivores and scavengers depend. They till and fertilize the soil. A single calf is born after 8.5-month gestation. Bands of female wildebeests are in control, leading the entire herd towards new grasslands. In the mid-20th century, the wildebeest population was decimated. The herd was cut down to one third of its normal size because of the rinderpest viruses (a variant of the measles virus). It originated and was spread from domestic livestock. As a result of loss of the grazing animals the grass lands grew uncontrolled. This over-growth subsequently changed the natural fire regime to an intense wildfire which burned nearly the entire Serengeti. This was an ecological disaster. Millions of domestic animals also died. Plant and animal species collapsed. Because of a massive human intervention including vaccination and quarantine the wildebeest population has been transformed. The Serengeti and Maasai Mara have been magnificently rewilded and the population of these animals is back to a stable 1.5 M with no disease detected in the last 8 years. Perhaps my 30 year wait to go was helpful because it allowed the wilderness more time to recover.

View to the south where the spread of animals seems endless.
Mixed wildebeest with zebra was a common observation
Animals on the move for the last hour and will probably continue for the next hour (My first video)

The sight of all these animals and the resource to feed and accommodate all of them provides a small but expanding view of the might of the ecosystem. At one time in the distant past this view would have been quite prosaic. Imagine Neanderthal or possibly the older Cro-Magnon people living with this type of annual migration. They would have been part of it. They would have been much earlier than our current view of history, but it probably looked like the American Great Basin to the First Peoples and early settlers of the Americas. We must appreciate that this area is just a few hundreds of miles from the Olduvei (Oldupai) gorge where Lewis and Mary Leakey (beginning in 1937) found fossilized hominoid remains dating back hundreds of thousands of years. (Pronconsul 25 million years old).  What were those people thinking when they saw this sight? The ancient hominoids and modern tribal peoples were and still are intimately connected with this environment. Their moment-to-moment survivals depended upon understanding this grand recipe and also the small, intimate details of their surroundings. The people of the Maasai tribe move their domesticated herds in synchrony with the wildlife, plants and rainfall. They know this because of their exposure to a multigenerational experience. They now participate in separation of their herds of domestic cattle and vaccination from Rinderpest and Foot and Mouth disease. We were so poorly prepared to comprehend systems as complex as this in just a few days.

I think that there are many lessons to be learned from this. For at least a million years hominoids and humans have learned that living in harmony with the constantly changing environment is a prerequisite to survival. The environment changes including geologic-like continental drift and volcanism. Weather changes, due to wind and rain/snow, land slides and floods, drought, temperature and storms. Species changes with mutations and natural selection. Human behavioral changes including perception and interpretation of surroundings, the value of group behavior and behavioral adaptation by creation of societies. Society changes with development of institutions like religion and governments. Behavior changes lead to exploration, discovery, invention and industrialization. The nomadic herders of today who live in near Stone Age conditions with cell phones will change. What changes will Space Age people make? We, the people of the space, information and atomic age have the ability to affect all of the aforementioned changes. We have the opportunity to do so because we live with disposable wealth and a discretionally directed time.

From the successful story of the rewilding of wildebeests in the Serengeti we have started on a new path. The wildebeest story is considered one of the most successful rewildings of our time. Rewilding efforts have been remarkably successful in Yellowstone, Spain, Argentina, Switzerland, ocean reef areas and many more. These efforts can not only save species and restore habitats but also fight the climate change crisis. Rewinding Florida is an active effort and a topic worthy of further exploration and discussion.

#Africa #wildebeest #Great Migration #migration #Maasai Mara. #Serengeti #rewilding #Mara river #stampede

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