Although a phylum is often spoken of as if it were a hard and fast entity, no satisfactory definition of a phylum exists. In fact, a phylum is perhaps best described as a statement of taxonomic ignorance. Consequently the number of phyla varies from author to author. The relationship between different phyla is increasingly well known, and larger clades can be erected to contain many of the phyla.
A clade (from ancient Greek κλάδος, klados, "branch") is a term used in modern alpha taxonomy, the scientific classification of living and fossil organisms, to describe a monophyletic group, defined as a group consisting of a single common ancestor and all its descendants.
above from wikipedia
In 1876 German engineer Nikolaus August Otto built a four-stroke gas engine, the most direct ancestor to today’s automobile engines.
I have the peculiar view that automobiles, viewed as inanimate machines, are in fact animated, and what animates them, is us!...and being animate, they follow the same laws of evolution that Darwin laid out...to survive, they must have our affection...kinda what's happened with dogs since the nineteenth century when breeding for appearance and skills began...I was surprised to learn most dog pedigree's date from that century....oh..this is far fetched I know!...but I spent all morning taking pics of my friends model cars....lighting courtesy of the Backyard Cedars, and the Bear Box for a platform...paper background by tientes.....cars are ingratiating...and if real ones like the ones above weren't so expensive, I'd certainly have one..or two!!....I used all the cameras....liked the digiscoped pics best, but these above, taken with the 1.8 50mm, showed the best detail on the decals....depth of field is maddening...have to look up model pics to see how it's done!!...sunny hot blue...Wolfie showed up at Last Chance...by the soups...same place I last saw her!...and back from a summer in Tuolumne...dont know but that was my intention six years ago...but got diverted....the pics in Elements were darkened about ten percent, and increased contrast ten percent, and sharpend twice....a kinda standard adjustment....the pics orignally are often softer and lighter...and I just like them darker with more contrast!...evolution at work...Wolfie asked, but no, I haven't seen a Ring Tail Cat yet....