1) Modern humans are no longer evolving significantly through natural selection and genetic mutations due to factors like central heating and abundant food. 2) Over the next 100 years, traits like poor eyesight and a tendency toward low birth weight may become more common as those with such traits are now more likely to survive and reproduce. 3) The appendix remains common only because having or lacking one no longer impacts survival rates, so there is no evolutionary pressure either way.

1. Geology 3 Field Assignment By April Chavarria

2. Homosapians How we Evolve: How are we evolving? The current theory of evolution is that over the generations, in our population, we get random genetic changes (mutations) in our DNA (genome). Most of these changes are harmless and they might have a chance to be fixed within a population at a low frequency. For centuries, writers have attempted to predict the future of the human race. Some have argued that we are destined to evolve into super-beings, others that we are turning into dim-witted goblins incapable of anything more demanding than watching TV. But according to a leading geneticist, both visions are wrong because human evolution has ground to a halt. Professor Steve Jones, of University College London, says the forces driving evolution - such as natural selection and genetic mutation - no longer play an important role in our lives. (www.dailymail.co.uk) The people living one million years from now, should Man survive, will resemble modern-day humans. In a harsh environment where people are competing to survive, natural selection is a potent force. So in Ice Age Britain, a mutation which gave a baby more resilience against the cold or famine also gave it a strong competitive edge, making it more likely to survive and pass its genes on to others. But in a modern world of central heating and plenty of food, the same mutation is far less likely to give a child any advantage There are some factors that can factor into our evolution in years to come. If we look at 100 years from now, it is an incredibly small period of time for evolution to work so any trends we may think we see may not turn out to become fixed in the population. But here are a few that might: Poor eyesight - having less than perfect vision no longer means that you are at a disadvantage because it can be corrected. So more people will survive with defective vision and pass on this to the next generation. Low birth weight / premature birth - as children who are born at low birth weight or prematurely now more often survive due to incubators and other medical interventions, any genetic tendency towards low birth weight or premature birth may become fixed in the population. The appendix is a largely vestigial organ - it has minimal functionality (it may have some small function in combating infection). The reason we still have an appendix is that being born either with or without one makes no difference to our survival rate - therefore there is no evolutionary pressure to either retain it or discard it. (www.yahooanswers.com)

3. Food Hormones and evolution Early puberty in girls has been found to be associated with a higher risk for breast cancer. Height, weight, diet, exercise, and family history have all been found to influence age of puberty . Steroid hormones in food were suspected to cause early puberty in girls in some reports. However, exposure to higher than natural levels of steroid hormones through hormone-treated meat or poultry has never been documented. Large epidemiological studies have not been done to see whether or not early puberty in developing girls is associated with having eaten growth hormone-treated foods. A concern about an increase in cases of girls reaching puberty or menarche early (at age eight or younger) in Puerto Rico, led to an investigation in the early 1980s by the Centers for Disease Control (CDC). Samples of meat and chicken from Puerto Rico were tested for steroid hormone residues. One laboratory found a chicken sample from a local market to have higher than normal level of estrogen. Also, residues of zeranol were reported in the blood of some of the girls who had reached puberty early. However, these results could not be verified by other laboratories. Following CDC's investigation, USDA tested 150 to 200 beef, poultry and milk samples from Puerto Rico in 1985, and found no residues of DES, zeranol or estrogen in these samples. In another study in Italy, steroid hormone residues in beef and poultry in school meals were suspected as the cause of breast enlargement in very young girls and boys. However, the suspect beef and poultry samples were not available to test for the presence of hormones. Without proof that exposure to higher levels of steroid hormones occurred through food, it is not possible to conclude whether or not eating hormone-treated meat or poultry caused the breast enlargement in these cases. (www.cornell.edu) In these pictures, my daughter is only 16 years old.

4. Obesity and evolution Obesity - being obese no longer means being unable to escape a predator or defeat a rival in battleas in earlier stages of evolution. Any tendency towards obesity is likely to become fixed in the population. Obesity Statistics