Related Experiment Video
Updated: Jun 5, 2026
09:39
Cultivation of the Marine Pelagic Tunicate Dolioletta gegenbauri (Uljanin 1884) for Experimental Studies
Published on: August 9, 2019
Tunicates push the limits of animal evo-devo.
1The Scottish Oceans Institute, University of St Andrews, East Sands, UK. dekf@st-andrews.ac.uk
BMC Biology
|January 22, 2011
Summary
Chordates, including humans, possess a notochord, a defining feature. New research reveals surprising molecular genetic diversity in how this crucial embryonic structure develops across species.
Area of Science:
- Evolutionary Biology
- Developmental Biology
- Genetics
Background:
- The phylum Chordata, encompassing humans, is named after the notochord, a key shared characteristic.
- The notochord is present in all chordates during embryogenesis, with clear morphological homology.
- Previous understanding suggested less variation in the genetic underpinnings of notochord development.
Purpose of the Study:
- To investigate the molecular genetic basis of notochord development in chordates.
- To identify and characterize the variability in genes controlling notochord formation.
- To compare genetic pathways of notochord development across different chordate species.
Main Methods:
- Comparative genomics analysis of genes involved in notochord development.
- Embryological studies examining notochord formation in diverse chordate models.
- Molecular assays to assess gene expression patterns during embryogenesis.
Main Results:
- Significant variability discovered in the molecular genetics of notochord development.
- Identification of diverse gene sets and regulatory mechanisms across chordate taxa.
- Homologous structures may arise from distinct genetic pathways.
Conclusions:
- The genetic mechanisms underlying notochord development are more diverse than previously assumed.
- This variability has implications for understanding chordate evolution and development.
- Further research is needed to fully elucidate the genetic landscape of notochord formation.
Related Concept Videos
01:24Evolution of New Traits in Microbes
Microorganisms evolve rapidly due to their large population sizes and short generation times, often exhibiting measurable changes within days under laboratory conditions. Natural selection acts on standing genetic variation, enabling the retention and amplification of beneficial traits that confer fitness advantages in changing environments.Adaptive Pigment Regulation in RhodobacterIn Rhodobacter, a genus of purple non-sulfur bacteria, light-harvesting pigments such as bacteriochlorophyll and...
01:24Eukaryotic Evolution
The endosymbiont theory is the most widely accepted theory of eukaryotic evolution; however, its progression is still somewhat debated. According to the nucleus-first hypothesis, the ancestral prokaryote first evolved a membrane to enclose DNA and form the nucleus. Conversely, the mitochondria-first hypothesis suggests that the nucleus was formed after endosymbiosis of mitochondria.
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
01:54Convergent Evolution
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.The structures that arise from convergent evolution are called analogous structures. They are similar in function even if they are dissimilar in structure. Further, structures can be analogous while also...
01:16Tonicity in Animals
Tonicity describes the amount of solute in a solution. The measure of the tonicity of a solution, or the total amount of solutes dissolved in a specific amount of solution, is called its osmolarity. Three terms—hypotonic, isotonic, and hypertonic—are used to relate the osmolarity of a cell to the osmolarity of the extracellular fluid that contains the cells. In a hypotonic solution, such as tap water, the extracellular fluid has a lower concentration of solutes than the fluid inside the cell,...
00:59Tonicity in Animals
The tonicity of a solution determines if a cell gains or loses water in that solution. The tonicity depends on the permeability of the cell membrane for different solutes and the concentration of nonpenetrating solutes in the solution within and outside of the cell. If a semipermeable membrane hinders the passage of some solutes but allows water to follow its concentration gradient, water moves from the side with low osmolarity (i.e., less solute) to the side with higher osmolarity (i.e.,...
01:27Diversity of Protists II
Alveolates are a group of organisms recognized by the presence of alveoli, which are cytoplasmic sacs located beneath the cell membrane. While their function remains uncertain, alveoli may help regulate water balance by controlling how much water enters and leaves the cell. In dinoflagellates, these structures may serve as armor plates. There are three major types of alveolates: ciliates, which move using cilia; dinoflagellates, which use flagella for movement; and apicomplexans, which are...