Nav: Home

Life in marine driftwood: The case of driftwood specialist talitrids

December 20, 2017

Driftwood in the sea - either floating or stranded on beaches - is a common feature particularly in temperate regions. Large quantities of driftwood, termed driftwood depositories, may collect at the mouth of small streams associated with marshes and have been present for some 120 millennia - since the origin of flowering plants.

Once marine driftwood begins to decay, it undergoes a specific succession. Firstly, it is colonized by salt tolerant, wood degrading fungi and bacteria, along with a few invertebrates able to digest wood by producing native wood degrading enzymes. The latter include gribbles (isopods) and chelurid amphipods.

Driftwood hoppers (talitrids), as well as isopods, chilopods, insect larvae, some ants and termites, comprize the secondary colonizers. They are all characterized by their inability to utilize driftwood directly. Instead, they rely on symbiotic microflora for digestive purposes.

Within all talitrids, the driftwood hoppers count as few as seven species, most likely because they are extremely difficult to locate and, therefore, discover and describe. Apart from living in tiny burrows, they measure between 13 and <6 mm, which makes the latter the smallest known talitrid.

Having reviewed the driftwood specialized talitrids, Dr. David Wildish of the St. Andrews Biological Station, Canada, concludes that all seven known species demonstrate dwarfism based on slow metabolism and growth. Their sexual development begins earlier compared to faster growing related species. All of them are also characterized with reduced eye size and absence of dorsal pigment patterns.

In his review article published in the open access journal Zoosystematics and Evolution, the scientist confirms that dwarfism in driftwood hoppers has evolved due to poor diet, in turn resulting in slowed metabolism and growth. A further adaptive challenge is the empty gribble burrow size occupied by talitrids (burrow diameter between 0.6 to 5 mm) with the smaller ones being more widespread. Larger talitrids can only complete their life cycle in the larger burrows.

"The size gradient in gribble burrow diameter provides a satisfactory explanation for serial dwarfism within the driftwood talitrids and is why each species becomes successively smaller," explains the researcher.

Responsibility for first establishing the driftwood talitrid ecological grouping was made during graduate studies by David Wildish, London University, U.K., and Laura Pavesi, University of Rome, Italy. The two criteria for inclusion of a talitrid in the driftwood grouping was: behavioral fidelity to the occupied driftwood and that the food source was solely rotting driftwood (see references).

The larger talitrid family are small/medium in body length (< 30 mm) crustaceans with more than 400 species described in the world list. Ecological groupings within the family include marine/estuarine supralittoral wrack generalists, sand-burrowing, marsh-living and driftwood specialists. A few freshwater and many terrestrial species are also known.
-end-
Original source:

Wildish DJ (2017) Evolutionary ecology of driftwood talitrids: a review. Zoosystematics and Evolution 93(2): 353-361. https://doi.org/10.3897/zse.93.12582

Pensoft Publishers

Related Ants Articles:

Ants fight plant diseases
New research from Aarhus University shows that ants inhibit at least 14 different plant diseases.
Australian ants prepared for 'Insect Armageddon'
La Trobe University researchers have uncovered an exception to the global phenomenon known as 'Insect Armageddon' in the largest study of Australian insect populations conducted to date.
Timing is everything for the mutualistic relationship between ants and acacias
Ant-acacia plants attract ants by offering specialized food and hollow thorns in which the ants live, while the ant colony in turn defends its acacia against herbivores.
Robot-ants that can jump, communicate with each other and work together
A team of EPFL researchers has developed tiny 10-gram robots that are inspired by ants: they can communicate with each other, assign roles among themselves and complete complex tasks together.
From vibrations alone, acacia ants can tell nibbles from the wind
Researchers reporting in the journal Current Biology on Feb. 14 find that the ants of the acacia tree are tipped off to the presence of herbivores by vibrations that run throughout the trees when an animal gets too close or begins to chew.
Recruiting ants to fight weeds on the farm
Harvester ants that eat weed seeds on the soil's surface can help farmers manage weeds on their farms, according to an international team of researchers, who found that tilling less to preserve the ants could save farmers fuel and labor costs, as well as preserve water and improve soil quality.
For ants, unity is strength -- and health
When a pathogen enters their colony, ants change their behavior to avoid the outbreak of disease.
How plants evolved to make ants their servants
Plants have evolved ways to make ants defend them from attacks and spread their seeds, and this new study shows how it happened.
The making of soldier ants
Scientists at McGill have found the answer to a question that perplexed Charles Darwin.
Desert ants have an amazing odor memory
Desert ants can quickly learn many different food odors and remember them for the rest of their lives.
More Ants News and Ants Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#538 Nobels and Astrophysics
This week we start with this year's physics Nobel Prize awarded to Jim Peebles, Michel Mayor, and Didier Queloz and finish with a discussion of the Nobel Prizes as a way to award and highlight important science. Are they still relevant? When science breakthroughs are built on the backs of hundreds -- and sometimes thousands -- of people's hard work, how do you pick just three to highlight? Join host Rachelle Saunders and astrophysicist, author, and science communicator Ethan Siegel for their chat about astrophysics and Nobel Prizes.