Evolutionary Designs of African Animals

Danielle LessoCollege of EngineeringPennsylvania State University

[mwanasimba]

During the dry season in the African grasslands, fiercecompetition exists among the animals for water

2 [cnx.org]

On the African savannah, predators of different sizes and strategies compete for large herd animals

This talk presents evolutionary designs of the largest, tallest, and fastest land animals on the planet

African Elephant

GiraffeCheetah

4

Modern elephants are the only remaining species of a vast order of animals

[www.nationalelephantcenter.org]

5

[www.defenders.org]

Elephants have changed size and shape over time

6

[www.smallkidshomework.com]

Using infrasonic sounds, elephants can communicate up to several kilometers apart

infrasonic

7

Human hearing range

[www.birds.cornell.edu]

Infrasonic communication is made possible by the elephant’s unique hyoid and trunk

time

8

[www.sciencdirect.com]

[www.birds.cornell.edu]

Elephants can communicate long distances by using seismic vibrations

9

Elephants can also physically generate seismic vibrations

[physiologyonline.physiology.org]

10

Seismic signals are picked up in the elephants’ wide feet

11 [physiologyonline.physiology.org]

Fatty Cushion

Elephants are masters of communication, thanks to key evolutionary designs

[www.pixabay.com]12

Reflection on the delivery of this section’s speakers

Giraffes are truly unique African mammals

15

[commons.wikimedia.org][flickr.com]

[zoo.org]

Evolutionary designs help giraffes survive in the dangerous African savannah

[Fore, Himes, Thomas; Dr. Eric Chudler]16

The coat of the giraffe aids in camouflage and parasite protection

[commons.wikimedia.org]

17

benzene

p-cresol

[Fore, Himes, Thomas]

Giraffes’ coats also play a role in thermoregulation

18

[commons.wikimedia.org]

[universalhealthcarela.com]

Sites of thermoregulation

The circulatory system of giraffes overcomes the challenges posed by the animal’s height

19

[panzajpanal.pl]

Valves in the neck arteries keep giraffes from passing out when they have to live their lift heads quickly

20

[panzajpanal.pl]

[wiki.hicksvilleschools.org]

Characteristic height and good eyesight are also key to survival

21 [Fore, Himes, Thomas]

RightLeft

Both

The giraffe is very capable of survival, thanks to evolutionary designs

22 [commons.wikimedia.org]

Reflection on the delivery of this section’s speakers

[en.wikipedia.org]25

Cheetahs have evolved into excellent hunters

[commons.wikimedia.org]

[wildencounters.net][flickr.com]

[pixabay.com]

A cheetah is a great hunter because of its speed, keen senses, and clever strategies

[flickr.com]

Speed Senses

[wildencounters.net]

26[pixabay.com]

Strategies

A cheetah has an extremely flexible spine, powering its long stride

[youtube.com]

27

[flickr.com]

The long tails of cheetahs allow them to make quick turns, while their claws provide traction

[art.com]

28

A cheetah relies on both its eyesight and its hearing to locate and stalk prey

29[philtulga.com]

[flickr.com]

The cheetah uses strategy to complement its physical advantages during hunting

30

[worldnomads.com]

There are drawbacks to being the fastest land animal

[www.wildencounters.net]

31

Even with the drawbacks, the cheetah is a unique predator because of its evolutionary design

32 [flickr.com]

In summary, evolutionary designs have allowed elephants, giraffes, and cheetahs to survive in extreme conditions

African Elephant

Giraffe33

Cheetah

However, man poses challenges to these species that evolutionary change might not be able to overcome

34

[Pringle]

[U.S. Fish and Wildlife Service]

Reflection on the delivery of this section’s speakers