Interesting two questions. I am not aware that consensus science shows Mars ever had life but reports from the past certainly seem to show this. Originally published in July 1907, “If vegetation exists on Mars, as Prof. Lowell would have us believe, the existence of a flora is ground for suspecting a fauna. On Mars we find ourselves confronted in the canals and oases by precisely the appearance which the planet should show if it is an inhabited world. Dearth of water is the key to the character of the canals. The only available water on Mars is that coming from the semi-annual melting at the one or the other cap of snow. If there are intelligent beings on Mars, they must find some means of conducting the scant supply of water from the poles to the centers of populations.” —Scientific American, July 1907 More gems from Scientific American’s first 175 years can be found on our shiny anniversary page."
Here is another life on Mars report from 1943. Originally published in July 1943 “If, as appears to be probable, vegetation exists on Mars, life has developed on two out of the three planets in our system where it has any chance to do so. With this as a guide, it appears now to be probable that the whole number of inhabited worlds within the Galaxy is considerable. To think of thousands, or even more, now appears far more reasonable than to suppose that our planet alone is the abode of life and reason. What the forms of life might be on these many worlds is a question before which even the most speculative mind may quail. Imagination, in the absence of more knowledge of the nature of life than we now possess, is unequal to the task. There is no reason, however, against supposing that, under favorable conditions, organisms may have evolved which equal or surpass man in reason and knowledge of Nature. And, let us hope, in harmony among themselves!”
—Scientific American, July 1943