Heteronomous annulation
Heteronomous annulation is a characteristic of some arthropods. It means that segments are differentiated from one another, each having different form so as to serve a different function – for instance, using some limbs for walking and others for feeding.
The trait is first observed in the armoured lobopods.[1] It is thought to be the precursor to segmentation in arthropods, and perhaps resulted from the need to produce serially repeated defensive structures (spines).[2] It can be studied using homeotic genes. [1] It is believed to be a trait found in the most recent common ancestor of Panarthropoda.[3]
References
[edit]- 1 2 Fortey, Richard; Thomas, Richard (1998). Arthropod Relationships. London: Chapman & Hall. ISBN 0-412-75420-7.
- ↑ Budd, Graham E. (2001). "Why are arthropods segmented?". Evolution & Development. 3 (5): 332–42. doi:10.1046/j.1525-142X.2001.01041.x. PMID 11710765. S2CID 37935884.
- ↑ Giribet, Gonzalo; Edgecombe, Gregory D. (September 2017). "Current Understanding of Ecdysozoa and its Internal Phylogenetic Relationships". Integrative and Comparative Biology. 57 (3): 455–466. doi:10.1093/icb/icx072. PMID 28957525.