1) Hardening of the shell in presence of Asian shore crab
Describe the adaptation
In the 1980’s the Asian shore crab arrived in the waters around New England, and it quickly became one of the most dominant crab species in New England (Science Daily, 2006). However, the blue mussel that is native to the are has evolved to defend itself against the dominant crab which eat the mussels by crushing their shells. The favorable adaptation of the crab is its ability to thicken its shell in when an Asian shore crab comes close to it.
Classify these adaptations as physiological, morphological, or behavioral.
The adaptation of the mussel to thicken its shell when in the presence of an Asian shore crab is a morphological adaptation because the physical form of the mussel changes.
Explain how the adaptation has improved upon the fitness of the organism.
The adaptation has improved upon the fitness of the organism because if it were not for the adaptation the mussel will easily be crushed by the crabs and eaten. Because of the adaptation, the mussel can harden its shell to prevent the crabs from breaking its shell, and therefore it can not be eaten by the crabs.
Relate at least one of the adaptations to a “theme of biology” that is not connected to evolution. In other words, do not use either the unity or diversity of life as your theme.
This adaptation can relate back to the theme of the correlation of structure and function insofar as the structure of the mussels shell has adapted its function. The crabs without the adaptation to harden and thicken their shells when in the presence die out because they can be eaten, but the ones with the adaptation live on to reproduce and to pass on the genes that allow the mussel to harden their shells when they sense an Asian shore crab. The structure of the shell of the mussel has evolved so that its function now protects it from the shore crabs.
Protecting against the
Bibliography: University of New Hampshire (2006, August 11). Mussels Evolve Quickly To Defend Against Invasive Crabs. ScienceDaily. Retrieved April 14, 2013, from http:// www.sciencedaily.com/releases/2006/08/060811091251.htm This website described the mussels adaptation of hardening its shell in the presence of the Asian shore crab. The site explains the experiments scientists used to prove that the mussels were in fact evolving, and it also provided a detailed summary of the adaptation of the mussels. Nordsieck, R. (n.d.). Mussels and Clams (Bivalvia). The Living World of Molluscs. Retrieved April 15, 2013, from http://molluscs.at/bivalvia/index.html?/bivalvia/ common_mussel.html This website provided the information on the mussels ability to tie down the predatory snails and information on the mussels behavior of forming mussels beds. It also has the information regarding how the mussel bed is favorable to the fertilization of the sperm and egg of the mussel.