Abstract The American lobster (Homarus americanusMilne Edwards, 1837) is an ecologically and economically valuable invertebrate in the Northwest Atlantic. Its geographic range is shifting northward due to ocean warming. While extensive research on the thermal tolerance of this species has been performed on adults and postlarvae, there have been few studies focused on its multiple early developmental stages. We applied transcriptomics to investigate transcriptional changes in laboratory-reared American lobster developmental stages I through V. Changes in gene expression were contextualized in the ontogenetic shifts in distribution that these different life history stages experience, with highly active stage IV exhibiting increased cellular metabolism and shell-building processes. We identified differential expression of transcripts related to thermal and UV stress in planktonic stages I-IV compared to benthic stage V, which suggests innate molecular defenses against these stressors. Together, these findings further our understanding of crustacean development in the context of climate change and can be used to inform population distribution modeling efforts. They also provide evidence for the need to investigate the potential trade-offs associated with responding to a changing environment on a stage-by-stage basis. 
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                            Overcoming life stage‐centric biases illuminates arthropod diversity, systematics and biology
                        
                    
    
            Abstract Synthetic studies of arthropod systematics and biodiversity are hindered by overreliance on ‘preferred’ semaphoronts, those life stages (typically adult males) that provide the most taxonomically distinctive characters. However, modern sequence‐based methods for inventory have no such limitations and permit incorporation of any and all representatives of a species. Here, we briefly review the growth and potential of these approaches to faunistic and systematic studies and share results from our own recent work that illustrate the value that other morphs, immature stages and females added to these studies. 
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                            - Award ID(s):
- 1916263
- PAR ID:
- 10512220
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Systematic Entomology
- Volume:
- 49
- Issue:
- 3
- ISSN:
- 0307-6970
- Format(s):
- Medium: X Size: p. 345-354
- Size(s):
- p. 345-354
- Sponsoring Org:
- National Science Foundation
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