Mimicry in individual human behavior can be seen as a flattery. In commerce, mimicry may be explained as a marketing ploy. However, it could be positive destiny when we're talking about resource efficient cars. First, lets try an explanation from a life science view: Muellerian mimicry, named for Fritz Mueller, a German zoologist, allows a stacked comparison of the Toyota Echo and Chevrolet Aveo (tongue in cheek with our adjectives here). Muellerian mimicry refers to two species that are mimics of each other with conspicuous warning coloration [outward design elements appealing to TreeHuggers], also known as aposematic coloration. Thus, all mimics share the benefits of the coloration [outward design elements]since the all predators [customers] will recognize the characteristics more easily. At first glance, can you guess which one is which?
Both rate mileage in the mid to high thirties, and are priced starting in the low to mid teens, depending on extras.
As an alernate explanation of the apparent convergence of outward form, we present a more mechanistic explanation as well.
Highly resource efficient cars have fewer marketable shape and form choices. This is due to engineering constraints that flow from reduced vehicular size and weight as needed to increase resoource efficiency in both manufacturing and use phase of the product. The limit of design form choice, which seems to have been approached simultaneously in both models, has a standard deviation that may later widen only through the introduction of transformative technologies: i.e. carbon fiber based structural elements; drive by wire,solar gain reducing glass.