An alarming message about deodorant use and breast cancer began circulating on the Internet in the 1990s, spread via e-mail and message-board postings. It continues to resurface now and again and causes a great deal of concern about the safety of items many of us use every day. So let's take a look at the evidence.
How long have sharks been in existence? A: Geological records show that modern shark species have existed for between 201 million and 174 million years. Earlier fish species similar to sharks existed as early as between 419 million and 359 million years ago.
The life-span of tiger sharks in the wild is considered to be 27 years in average, even though some may live up to 50 years of age. As with other species, tiger sharks in captivity do not live as extensive as in wildlife reaching only 17 to 20 years. Some experts presume that the lifespan of the Great White Sharks is approximately 30 years (Levine, 1988) but other research indicates that they can reach up to 40 years.