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Looking
at Life Today
Modern
reptiles are cousins to the dinosaurs. Crocodiles are among the
most ferocious reptiles alive today.
Reptiles suffer
from fewer diseases than warm-blooded animals, but reptiles do get
sick. For example, an epidemic of Entamoeba invadens caused by the
parasite amoebas swept through the London Zoo and killed a large
number of reptiles and snakes. Many amphibians and reptiles have
a gland, the Harderian gland, next to their eyes that washes excess
salt out of their bodies. The glands form droplets sometimes called
"crocodile tears." These glands can become infected, sometimes
causing the animal to lose its sight. Snakes get blood parasites
from tick bites.
 Many
scientists think birds are the descendants of dinosaurs. This emu
walks like bipedal ("two-footed") dinosaurs. Just imagine
this bird with a longer tail, a tooth-filled mouth instead of a
beak, and (maybe) no feathers; and you have a small-scale version
of a T-Rex!
Birds suffer
from many more diseases than reptiles. Chickens get a disease called
Rous sarcoma, which causes tumors. Chickens and turkeys also suffer
from diseases caused by parasites. One such disease, called Blackhead,
spread from captive turkeys to wild heath hens in the eastern United
States during the early 1900s.The heath hens had already been significantly
reduced in number due to hunting and loss of habitat. Catching blackhead
disease helped pushed them to extinction. Image
© 1999 -www.arttoday.com
So, did dinosaurs
get sick? Probably, yes--from the same kinds of diseases
that make people sick.
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