Hobbes Choice wrote:
Here's something interesting; there is no such thing as a "Martian Meteorite". lumps of rock found in Antartica, have attracted this curious description, but it implies much more than it is worth. Rocks from Mars do not just leap off the planet with life on them and happily make their way to earth.

nasa.gov wrote:The fourteen martian meteorites are igneous rocks of five different varieties. They crystallized from molten lava near Mars’ surface. The group is unusual compared to typical igneous meteorites from asteroids. All but one are younger (1.3 billions years old or less) and have higher contents of water and gases than meteorites from asteroids. The conclusive evidence that these meteorites originated on Mars came from the measurement of gases trapped in one meteorite’s interior. These trapped gases, now confirmed in other meteorites, match those that the Viking lander measured in the martian atmosphere.

“In the early 20th century the need to find this missing link became so desperate that an elaborate hoax was created. Piltdown Man (“discovered” in 1912) was believed to be genuine for over 40 years. In fact is was faked using a Medieval human skull, the jaw bone of an orangutan and fossilized teeth from a chimpanzee, and then “aged” by soaking it in acid and staining it with an iron solution.” ― Ellis Silver, Humans are not from Earth: a scientific evaluation of the evidence

Here are his genuine reasons:

The sun hurts our eyes
The sun kills us (gives us skin cancer)
Some people suffer from seasonal affective disorder (SAD)
We commonly suffer from bad backs
We have 223 apparently unique genes
There no 'missing link' the fossil record
We lack the ability to sense the Earth's magnetic fields (and use to get a sense of direction)
We lack body hair
Some people suffer from hay fever and asthma
We like eating tasty food that is sometimes bad for us
We breed too much, resulting in overpopulation
We lack natural defenses against large predators
We're destroying the environment
The technological leap from protohumans to modern day is just too great
We suffer from a host of chronic illness.

So, basically: I don't understand; therefore aliens.