Human and Animal Lifespans

Source: Wikipedia (human), Tesarta.com (animal)

Humans by EraAverage Lifespan at Birth (years)
Upper Paleolithic33*
Neolithic20
Bronze Age18
Classical Greece20-30
Classical Rome20-30
Pre-Columbian North America25-35
Medieval Islamic Caliphate35+**
Medieval Britain20-30
Early 20th Century30-40
Current world average66.12 (2008 est.)

*: At age 15: 39 (to age 54)
**: The average lifespans of the scholarly class were 59–84.3 years in the Middle East and 69–75 in Islamic Spain.

These represent estimates of the life expectancies of the population as a whole. In many instances life expectancy varied considerably according to class and gender. Life expectancy rises sharply in all cases for those who reach puberty. All statistics include infant mortality, but not miscarriage or abortion.

The following information is compiled from a number of sources. Additional lifespans may be found at Dr. Bob's All Creature Site.

Animal (General)Maximum Lifespan (years)*
Mammals 
Bull28
Camel50
Cat25
Cow22
Deer35
Dog, large10
Dog, small17
Donkey45
Elephant70
Fox14
Goat15
Hare10
Horse40
Lion35
Mouse4
Ox20
Pig, wild25
Rabbit9
Sheep15
Tiger22
Wolf18
Birds 
Amazon Parrot80
Blackbird18
Chicken15
Pigeon26
Macaw50
Reptiles 
American Box Turtle123
Crocodile45
Galapagos Land Tortoise193
Rattlesnake22
Insects 
Ant, queen3
Ant, worker0.5
Bee, queen5
Bee, worker1

*: This is not the absolute maximum lifespan. However, there is an upper age limit at which the vast majority of animals will die. Animals living past that age are exceptions, and aside from being old and wise are also incredibly snappy dressers.