26.8.2 The Rest of us Also Use Gastrointestinal Symbiont
Microbes
Symbiotic interactions with intestinal microbes are a critical health component for all
animals. Some flatworms have trophosomes as do the Riftia. Perhaps more than 10%
of insects contain bacteriocytes within their midgut epithelium that house endosymbiont microorganisms, including bacteria and fungi which help with digestion and
provide essential compounds such as amino acids. The rest of us animals depend
upon mutualistic symbiotic microorganisms that reside within the lumen of our
intestines and some of those microbes are in biofilms associated with mucosa. People
tend to think of mucosal biofilms solely in association with pathogenesis, but the
gastrointestinal microbes that contribute to our health generally also represent
mucosal biofilms. Extending from that last thought, I would suggest the publication
by Hillman et al. (2017) in which those authors presented a comparative study on the
gastrointestinal microbial ecology of mammals.
26.9 Luminescent Bacterial Symbionts
There are many groups of animals, including teleosts (infraclass Teleostei) and squid
(subclass Coleoidea), that house luminescent bacterial symbionts within specialized
organs. Some squid may use their light organs as a form of camouflage against
predators. There are angler fish which house luminescent bacteria in their esca,
termed a lure, and the illumination from that organ serves to attract prey.
Fish belonging to the family Anomalopidae house luminescent bacteria in light
organs located below their eyes (Hendry et al. 2016; Hellinger et al. 2017). These
fish belong to the genera Anomalops, Photoblepharon, and Phthanophaneron.
Figure 26.34 is a photograph of Anomalops katoptron, which is called the splitfin
or two-fin flashlight fish. The Anomalopidae are capable of either revealing or
concealing the illumination, in effect blinking their light, and that activity has been
likened to the appearance of using a signal lamp or flashlight for sending Morse code
messages. These nocturnal fish have no equivalent to Morse code, but the intervals at
which they blink their light do vary in a way that has been associated with locating
zooplankton prey. The blinking of their light also may help these fish to group as a
school at night (Gruber et al. 2019).
26.10 Endosymbiotic Viruses
Organisms have mechanisms for acquiring and genomically incorporating DNA
from environmental sources (Bininda-Emonds et al. 2016).
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C. J. Hurst
Microbes
Symbiotic interactions with intestinal microbes are a critical health component for all
animals. Some flatworms have trophosomes as do the Riftia. Perhaps more than 10%
of insects contain bacteriocytes within their midgut epithelium that house endosymbiont microorganisms, including bacteria and fungi which help with digestion and
provide essential compounds such as amino acids. The rest of us animals depend
upon mutualistic symbiotic microorganisms that reside within the lumen of our
intestines and some of those microbes are in biofilms associated with mucosa. People
tend to think of mucosal biofilms solely in association with pathogenesis, but the
gastrointestinal microbes that contribute to our health generally also represent
mucosal biofilms. Extending from that last thought, I would suggest the publication
by Hillman et al. (2017) in which those authors presented a comparative study on the
gastrointestinal microbial ecology of mammals.
26.9 Luminescent Bacterial Symbionts
There are many groups of animals, including teleosts (infraclass Teleostei) and squid
(subclass Coleoidea), that house luminescent bacterial symbionts within specialized
organs. Some squid may use their light organs as a form of camouflage against
predators. There are angler fish which house luminescent bacteria in their esca,
termed a lure, and the illumination from that organ serves to attract prey.
Fish belonging to the family Anomalopidae house luminescent bacteria in light
organs located below their eyes (Hendry et al. 2016; Hellinger et al. 2017). These
fish belong to the genera Anomalops, Photoblepharon, and Phthanophaneron.
Figure 26.34 is a photograph of Anomalops katoptron, which is called the splitfin
or two-fin flashlight fish. The Anomalopidae are capable of either revealing or
concealing the illumination, in effect blinking their light, and that activity has been
likened to the appearance of using a signal lamp or flashlight for sending Morse code
messages. These nocturnal fish have no equivalent to Morse code, but the intervals at
which they blink their light do vary in a way that has been associated with locating
zooplankton prey. The blinking of their light also may help these fish to group as a
school at night (Gruber et al. 2019).
26.10 Endosymbiotic Viruses
Organisms have mechanisms for acquiring and genomically incorporating DNA
from environmental sources (Bininda-Emonds et al. 2016).
586
C. J. Hurst