Maybe it is not just sentimental. Perhaps the connection to "man's best friends" is literally in our heads.

Skull shape is a complex trait, involving multiple genes and their interactions. Thanks to standardized canine breeding, which documents more than 400 breeds worldwide, and their distinct morphological features, researchers can disentangle traits such as skull shape, which is often a breed-defining variation. 

Almost two years ago, I wrote an article entitled "What is life - Part 1" describing various aspects of life that dealt with the issues of "intent" and "purpose".  These are obviously heavily loaded terms, and represent a tremendous difficulty in defining life and trying to come to terms with the obvious and yet inexplicable behaviors we see.

Yet, we all recognize this type of behavior and biology even uses the term teleonomy to characterize this (1).

Want to feel small? Humans have been included in the most comprehensive tree of life to-date on placental mammals. And placental mammals are the largest branch of the mammalian family tree, with more than 5,100 living species. 

To many, DNA represents the definitive code which governs all life.  It has been compared to a sophisticated computer program from which every aspect of an individual organism is built.

Equally it has been stated that DNA is not destiny, so there is some basic recognition that DNA is not the absolute arbiter of everything biological.

An international team of researchers sequenced nuclear and mitochondrial DNA that had been extracted from the leg of an early modern human from Tianyuan Cave near Beijing, China and found that the human from 40,000 years in China is related to many people on multiple continents.

Analyses of this individual's DNA showed that the Tianyuan human shared a common origin with the ancestors of many present-day Asians and Native Americans. In addition, the researchers found that the proportion of Neanderthal and Denisovan-DNA in this early modern human is not higher than in people living in this region nowadays.

“It is demonstrable,” said he, “that things cannot be otherwise than as they are; for as all things have been created for some end, they must necessarily be created for the best end. Observe, for instance, the nose is formed for spectacles, therefore we wear spectacles. The legs are visibly designed for stockings, accordingly we wear stockings.”

- Candide by Voltaire

Humans are unique among the great apes (of which we are one) in various ways. One of them is our possession of a very long Achilles tendon, which is quite short in chimpanzees, gorillas, and orangutans.

This past May, I was fortunate enough to take part in a conference in Venice, Italy, which was a retrospective on the legacy of famous paleontologist and author Stephen Jay Gould 10 years after his death. The choice of Venice as the conference venue was a nod to one of Gould’s most famous and influential papers, “The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme“, which he co-authored with Richard Lewontin in 1979.

Neil Shubin alert: Researchers have found evidence that the development of hands and feet occurred through the gain of new DNA elements that activate particular genes - and they used a zebrafish to show it. 

The transition from water to land was obviously a major event in the history of vertebrate
life. In order to understand how fins may have evolved into limbs, researchers introduced extra Hoxd13, a gene known to play a role in distinguishing body parts, at the tip of a zebrafish embryo's fin. This led to the generation of new cartilage tissue and the reduction of fin tissue—changes that are similar to key aspects of land-animal limb development.