Beaks | 2014, ongoing project
Anser anser, Graylag Goose
Lightboxes with Diasec mounted Duratrans 64,5 x 70 x 10cm
In chicken embryos, we intervened to cause the beaks to develop into shapes seen in other birds.
The potential to generate beaks of different sizes and shapes by perturbing morphogenesis at different stages of the developing embryo is used to create a series of various shaped beaks in chicken embryos.
The outcomes raise questions about the expression of traits that are considered to be dictated by one's genetic makeup. How is evolution structured if a chicken embryo is able to develop a parrot-type beak without genetic change? This alteration is even outside the range of triangular forms seen in the famous Darwin's finches.
The induction of beaks shaped like those of other bird generated by perturbing development of the chicken embryo shows that these alternative beak shapes were not necessarily the fruit of a continuous and gradual evolutionary reshaping. They may have instead originated suddenly, by alteration of the physical forces underlying beak morphogenesis. That is, they are morphological outcomes within the developmental repertoire of the chicken.
The most widely held understanding of evolution has been based on Darwin's concept of natural selection. The production of variously shaped beaks in a single generation is antithetical to this view, since it is not the result of a gradual, gene-based reshaping process. In these experiments the different forms in fact arise in an animal (the chicken) with a constant genome.
Diemut Strebe in collaboration with Stuart Newman and colleagues, New York Medical College