Complex critters say fish, cockroaches, rats on up most likely do not exist on Mars anymore.

We do know that Mars had (past tense) abundant water, we see evidence of ocean basins and even riverbeds.

How dense was Mar's atmosphere? No one knows. We have several great guesses, however they are just that - guesses.

Earth and Mars are very similar in size and mass thus gravity. However Venus's atmosphere is about 93 times more dense than Earth's. Mar's could have had a substantially denser atmosphere at one time, enough to support complex life forms and a complex ecology with sufficient biodiversity to even have intelligent life at one point in its history. Or Mars could have had an atmospheric pressure too low for anything more than oceans of microscopic lifeforms with lichen and moss only. We do not know.

Mars is now dead. Sorry if life still exists on Mars it is microbial at best - maybe as complex as lichen or moss - maybe.

Mars is a strange world, one that still barely exists at triple point. This means that its atmosphere is still dense enough with temperature ranges high enough to contain water in all three states, solid (ice), liquid and vapor. It is also small enough to where we could, even with our presently limited technology bring it back to life... of a sort.

It is also a planet that we should NOT be sending lots of space junk to until we can mount a manned mission capable of studying the virgin planet to detect life (microbial) before we contaminate it with earth microbes. Sadly we most likely have already contaminated it.

Life on Europa (The water moon) is highly probable and may be as complex as fish.

That is about all we can expect inside our own solar system.

As for life outside of the solar system. That depends on how often stable stars have terrestrial planets in their Goldilocks Zones and how stable those planets are. We now understand that the basic building blocks of life water and the chemicals of life itself are abundant in the universe.

Further we have confirmation that planets do form around other stars, granted all we have found thus far appear to be gas giants, however we are working on the technology to detect smaller terrestrial planets and will within the next 10 to 20 years have a list of stars with rocky planets. After that say another 50 years tops we will know if those planets have nitrogen/oxygen atmospheres. If they do then we will know that life does exist on them.

Oxygen rich atmospheres are a product of life. Oxygen tends to bind with other elements, life (plants to be specific) have mastered breaking the bond between the carbon and oxygen in carbon dioxide using the carbon for cell structure and releasing oxygen as a waste.

Tesla was a genius. There is no way I can say otherwise. However the line between genius and insanity is very, very fine. I believe that Tesla crossed that line more than once in his lifetime.

Others understood that Tesla walked that thin line and took advantage of that fact to abuse him while he lived. Thus I find it a wee bit difficult to believe that Tesla actually talked to Martians.

Andrew D. Basiago does well on the Rorschach test that we get in the way of images from Mars. Unfortunately every image he has is blurred, ill defined or has been doctored to the point where his interpretation is just an interpretation of the images.

I am moderate in most things, however when it comes to calling an image of what is most likely a rock a skull, a hand, an artifact of a past civilization when the image is too indistinct to make such a call I would stick with it is a geologic feature until such time that we get a close up image of it and or send a manned mission to Mars and have them return with the skull, artifact, what ever.

Mars died about a billion years ago. Her death was a slow and agonizing one and there should be no doubt that any civilization that could have been on Mars was not only wiped out by the processes leading to Mars death, but also wiped out by the billions of years of wind and sand erosion. Nothing a civilization can make can last billions of years on an active planet.