Tears Of The Cheetah


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Presentation targeted to teach students about genetic diversity - one of my favorite classes to teach at outreach programs.

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Tears Of The Cheetah

  1. 1. TEARS OF THE CHEETAH - a story of genetic diversity Dr Karobi Moitra , NCI Frederick
  2. 2. Where do cheetahs stand on the tree of life? Kingdom: Animalia Phylum : Chordata Class : Mammalia Order : Primates Order : Carnivora Family : Hominidae Family : Felidae Genus : Homo Genus: Acinonyx Species: H. sapiens Species: A. jubatus
  3. 3. Where did the name ‘cheetah’ come from ? Sanskrit word : Chitakayah - which means ‘variegated’ body - ‘marks or patches’’ Hindi - ‘Chitah’ English : Cheetah
  4. 4. Cheetah range : Africa: Niger, Sudan, Ethiopia, Kenya,Tanzania, Namibia, Botswana etc. Iran: Khorasan SE Asia: India? Pakistan?
  5. 5. Some cool cheetah facts : • Cheetah eat gazelles, impala, zebra, hare etc. • They hunt in early morning or late in the afternoon • They hunt in groups • Rely on vision not scent to hunt • Adult cheetahs weigh ~ 140lb • Total body length over 6ft • Have a distinct ‘tear’ streak
  6. 6. How fast can cheetah’s run ? Cheetah’s can run upto 75 mph (120km/h) for 1,500ft or 1min 30 secs. Acceleration: 1-64 mph in 3 secs
  7. 7. Cheetah Chatter The African cheetah population was down to around 15,000 wild cheetahs So conservationalists tried to breed them in captivity - this was very hard to do Also cheetah populations were very prone to disease, if a few cheetah were infected with a disease such as FIPV- feline infectious peritonitis virus, the rest become infected and die WHY?
  8. 8. Journey to Africa Mitch Bush (National Zoo) & David Wildt (NCI) boarded a plane to the DeWildt cheetah breeding center in Pretoria (South Africa) They collected blood samples from around 80 cheetahs and brought them back to Stephen O’Briens lab at NCI-Frederick for analysis.
  9. 9. Proteins in the cheetahs blood were separated and analyzed using a technique called : Protein Gel Electrophoresis
  10. 10. Protein Gel Electrophoresis
  11. 11. Mobility shifts (change in the position of a protein band) can identify the different types of enzyme variants in a cheetah blood sample Most animals have a 20-50% difference in specific blood proteins(enzymes) called allozymes because they are different varieties of the same protein
  12. 12. However, when Janice Martenson looked at the allozymes In the cheetah blood samples she found that cheetahs were Identical for 52 allozymes across the board.
  13. 13. What did this mean?
  14. 14. Cheetahs seemed to be almost genetic clones of each other….but more evidence was needed !
  16. 16. The double helix
  17. 17. Genetic diversity
  18. 18. Back to Africa ! MHC genes are extremely variable They are responsible for graft rejection Skin grafts from 6 unrelated cheetahs were done If these graft were accepted and grew it meant that these cheetahs were nearly genetically identical to each other = very little genetic diversity
  19. 19. All 6 cheetahs accepted the grafts
  20. 20. Most cheetahs are almost identical clones of each other ! That is why they are more susceptible to disease !
  21. 21. How did this happen?
  22. 22. The “Bottleneck Effect” 12,000ya Pleistocene Great mammal Extinction
  23. 23. Tears of the cheetah - the legend “A young female cheetah climbed into a warm cave to slumber through a harsh winter in Europe. When she and her cubs crept out in springtime, they met a different world, one in which the cheetahs were (almost) gone - victims of a global holocaust” ……and she cried for them
  24. 24. http://www.cheetahkids.com/ Save the cheetah !
  25. 25. References / Websites www.wikipedia.org www.cheetah.org www.cheetahkids.com/ Tears of the Cheetah by Stephen J . O’Brien