''Durvillaea'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of large
brown algae
Brown algae (singular: alga), comprising the class Phaeophyceae, are a large group of multicellular algae, including many seaweeds located in colder waters within the Northern Hemisphere. Brown algae are the major seaweeds of the temperate and po ...
in the
monotypic family
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...
Durvillaeaceae. All members of the genus are found in the southern hemisphere, including
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
,
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
,
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
, and various subantarctic islands.
''Durvillaea'', commonly known as southern bull kelps, occur on rocky, wave-exposed shorelines and provide a habitat for numerous intertidal organisms.
Many species exhibit a honeycomb-like structure in their fronds that provides buoyancy, which allows individuals detached from substrates to raft alive at sea, permitting dispersal for hundreds of days over thousands of kilometres.
''Durvillaea'' species have been used for clothing, tools and as a food source by many indigenous cultures throughout the South Pacific, and they continue to play a prominent role in
Chilean cuisine
Chilean cuisine stems mainly from the combination of traditional Spanish cuisine, Chilean Mapuche culture and local ingredients, with later important influences from other European cuisines, particularly from Germany, the United Kingdom and Fr ...
.
Common name and etymology
The common name for ''Durvillaea'' is southern bull kelp, although this is often shortened to bull kelp, which can generate confusion with the North Pacific
kelp
Kelps are large brown algae seaweeds that make up the order Laminariales. There are about 30 different genera. Despite its appearance, kelp is not a plant - it is a heterokont, a completely unrelated group of organisms.
Kelp grows in "underwat ...
species ''
Nereocystis luetkeana''.
The genus is named after French explorer
Jules Dumont d'Urville
Jules Sébastien César Dumont d'Urville (; 23 May 1790 – 8 May 1842) was a French explorer and naval officer who explored the south and western Pacific, Australia, New Zealand, and Antarctica. As a botanist and cartographer, he gave his nam ...
(1790-1842).
Description
![DantarcticaCl04](https://upload.wikimedia.org/wikipedia/commons/f/f8/DantarcticaCl04.JPG)
''Durvillaea'' species are characterised by their prolific growth and plastic morphology.
Two species, ''
D. antarctica'' and ''
D. poha'' are buoyant due to a honeycomb-like structure in the fronds of the kelp that holds air.
When these species detach from the seabed, this buoyancy allows for individuals to drift for substantial distances, permitting
long distance dispersal.
In contrast, species as ''
D. willana'' lack such 'honeycomb' tissue and are non-buoyant, preventing the individuals from moving long distances.
Ecology
''Durvillaea'' bull kelp grow within intertidal and shallow subtidal areas, typically on rocky wave-exposed coastal sites.
''
D. antarctica'' and ''
D. poha'' are intertidal, whereas ''
D. willana'' is subtidal (to 6 m depths).
Intertidal species can grow at the uppermost limit of the intertidal zone if there is sufficient wave wash.
Species can withstand a high level of disturbance from wave action,
although storms can remove individuals from substrates.
Epibionts, parasites and rafting
![Durvillaea beachcast1](https://upload.wikimedia.org/wikipedia/commons/e/e1/Durvillaea_beachcast1.jpg)
Holdfasts of ''
D. antarctica'' and other species are often inhabited by a diverse array of
epifaunal and infaunal invertebrates, many of which burrow into and graze on the kelp.
In New Zealand, species that inhabit ''Durvillaea'' include the sea-star ''
Anasterias suteri
''Anasterias'' is a genus of starfish in the family Asteriidae
The Asteriidae are a diverse family of Asteroidea (sea stars) in the order Forcipulatida. It is one of three families in the order Forcipulatida.
Genera
The World Register of M ...
'',
crustaceans such as ''
Parawaldeckia kidderi
''Parawaldeckia'' is a genus of amphipod crustacean in the family, Lysianassidae. and was first described by Thomas Roscoe Rede Stebbing in 1910. The type species is '' Parawaldeckia thomsoni'' (first described in 1906 by Stebbing as ''Nannonyx ...
'', ''
P. karaka'',
and the
gribbles ''
Limnoria segnis
''Limnoria'' is a genus of isopods from the family Limnoriidae.
Species
*'' Limnoria agrostisa'' Cookson, 1991
*'' Limnoria algarum'' Menzies, 1957
*'' Limnoria andamanensis'' Rao & Ganapati, 1969
*'' Limnoria antarctica'' Pfeffer, 1887
*' ...
''
and ''
L. stephenseni'', as well as the
molluscs
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is estim ...
''
Cantharidus roseus'', ''
Onchidella marginata'',
''
Onithochiton neglectus
''Onithochiton'' is a genus of chitons in the subfamily Toniciinae of the family Chitonidae, which is distributed from Australia and New Zealand to South Africa. MolluscaBase eds. (2021). MolluscaBase. Onithochiton Gray, 1847. Accessed through ...
'',
and ''
Sypharochiton sinclairi'',
and the spider ''
Desis marina''.
[Vink, C., McQuillan, B., Simpson, A., & Correa-Garhwal, S. (2017). The marine spider, ''Desis marina'' (Araneae: Desidae): new observations and localities. ''The Weta, 51'', 71-79. Retrieved from http://publications.ento.org.nz/index.php/weta/article/view/167]
''Durvillaea'' individuals can detach from substrates, particularly during storms. Once detached, buoyant species such as ''
D. antarctica'' and ''
D. poha'' can float as rafts, and can travel vast distances at sea, driven by ocean currents.
Specimens of ''D. antarctica'' have been found to float for up to 210 days, during which time high wind speeds transport kelp rafts up to 10,000 km.
Environmental factors such as temperature, solar radiation and surface winds (all of which vary with latitude) affect buoyancy of southern bull kelp rafts and their rate of travel.
Rafts of ''D. antarctica'' are more likely to disperse offshore if individuals detach during outgoing tides during autumn and winter.
Rafts of Kelp-associated invertebrates can be transported inside of drifting kelp holdfasts, potentially leading to long-distance dispersal and a significant impact upon the population genetic structure of the invertebrate species.
Rafts of ''Durvillaea'' can be colonised by the
goose barnacles
Goose barnacles, also called stalked barnacles or gooseneck barnacles, are filter-feeding crustaceans that live attached to hard surfaces of rocks and flotsam in the ocean intertidal zone. Goose barnacles formerly made up the taxonomic order Pe ...
''
Lepas australis
''Lepas australis'' is a species of goose barnacle in the family Lepadidae. It is found in New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North ...
'' and ''
L. pectinata''. Beachcast, decomposing bull-kelp is colonised and consumed by a wide variety of invertebrates including sandhoppers ''
Bellorchestia quoyana'',
and kelp flies ''
Chaetocoelopa littoralis''.
Other seaweeds including ''
Gelidium lingulatum'', ''
G. rex'', ''
Corallina officinalis
''Corallina officinalis'' is a calcareous red seaweed which grows in the lower and mid-littoral zones on rocky shores.
It is primarily found growing around the rims of tide pools, but can be found in shallow crevices anywhere on the rocky shor ...
'' var. ''chilensis'', and ''
Lessonia spicata
Lessonia may refer to:
* ''Lessonia'' (alga), a genus in the family Lessoniaceae
* ''Lessonia'' (bird), a genus in the family Tyrannidae
* ''Lessonia'', a synonym for '' Aglaura,'' a genus of hydrozoans
{{genus disambiguation ...
'' also grow as epiphytes in the holdfasts of ''D. antarctica''.
Rafting on ''D. antarctica'' appears to have influenced the dispersal and phylogeography of these non-buoyant species.
In New Zealand, ''Durvillaea'' fronds can also be infected by the obligate red algal epiphyte ''
Pyrophyllon subtumens
''Pyrophyllon subtumens'' is an obligate red algal epiphyte of ''Durvillaea
''Durvillaea'' is a genus of large brown algae in the monotypic family Durvillaeaceae. All members of the genus are found in the southern hemisphere, including Austr ...
''
(J. Agardh ex R.M. Laing) W.A. Nelson 2003.
Fronds of ''
D. antarctica'' can be infected by an endophytic, phaeophycean algal parasite ''
Herpodiscus durvillaeae''
(Lindauer) G.R. South.
Fronds can also be infected ''
Maullinia
''Maullinia'' is a genus of intracellular, protistan parasites that infect brown algae (Phaeophyceae).
Distribution
''Maullinia'' has been found in brown macroalgae across the Southern Hemisphere, including Chile, the Falkland Islands, Australia ...
'', a genus of intracellular,
protistan
A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the excl ...
parasites.
Based on genetic evidence, both ''H. durvillaeae'' and ''Maullinia'' have likely been dispersed across the Southern Hemisphere via rafting bull kelp.
Environmental stressors
Increased temperatures and heatwaves, increased sedimentation, and invasive species (such as ''
Undaria pinnatifida'') are sources of
physiological stress
Stress, either physiological, biological or psychological, is an organism's response to a stressor such as an environmental condition. Stress is the body's method of reacting to a condition such as a threat, challenge or physical and psycholo ...
and disturbance for members of the genus.
A marine heatwave in the summer of 2017/18 appears to have caused the
local extinction
Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...
of multiple ''Durvillaea'' species at Pile Bay, on the
Banks Peninsula
Banks Peninsula is a peninsula of volcanic origin on the east coast of the South Island of New Zealand. It has an area of approximately and encompasses two large harbours and many smaller bays and coves. The South Island's largest cit ...
.
Once the kelp was extirpated, the invasive kelp ''Undaria pinnatifida'' recruited in high densities.
Disturbance from earthquake uplift
Earthquake uplift that raises the
intertidal zone
The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species o ...
by as little as 1.5 metres can cause ''Durvillaea'' bull kelp to die off in large numbers.
Increased sedimentation following landslides caused by earthquakes is also detrimental.
Once an area is cleared of ''Durvillaea'' following an uplift event, the bull kelp that re-colonises the area can potentially originate from genetically distinct populations far outside the uplift zone, spread via long distance-dispersal.
Intertidal species of ''Durvillaea'' can be used to estimate earthquake uplift height, with comparable results to traditional methods such as
lidar
Lidar (, also LIDAR, or LiDAR; sometimes LADAR) is a method for determining ranges (variable distance) by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver. It can also be ...
.
However, since ''Durvillaea'' holdfasts often grow at the uppermost limit of the intertidal zone, these uplift estimates are slightly less accurate compared to measures derived from other intertidal kelp such as ''
Carpophyllum maschalocarpum''.
Chile
The
2010 Chile earthquake caused significant coastal uplift (~0.2 to 3.1 m), particularly around the Gulf of Arauco, Santa María Island and the Bay of Concepción.
This uplift caused large scale die offs of ''
D. antarctica'' and dramatically affected the intertidal community.
The damage to infrastructure and ecological disturbance caused by the earthquake was assessed to be particularly damaging for seaweed gatherers and cochayuyo harvest.
New Zealand
Akatore
''Duvillaea'' bull kelp diversity appears to have been affected by uplift along the
Akatore fault zone.
Phylogeographic
Phylogeography is the study of the historical processes that may be responsible for the past to present geographic distributions of genealogical lineages. This is accomplished by considering the geographic distribution of individuals in light of ge ...
analyses using
mitochondrial COX1
Cytochrome c oxidase I (COX1) also known as mitochondrially encoded cytochrome c oxidase I (MT-CO1) is a protein that in humans is encoded by the ''MT-CO1'' gene. In other eukaryotes, the gene is called ''COX1'', ''CO1'', or ''COI''. Cytochro ...
sequence data and
genotyping by sequencing In the field of genetic sequencing, genotyping by sequencing, also called GBS, is a method to discover single nucleotide polymorphisms (SNP) in order to perform genotyping studies, such as genome-wide association studies (GWAS). GBS uses restrictio ...
data for thousands of anonymous
nuclear
Nuclear may refer to:
Physics
Relating to the nucleus of the atom:
* Nuclear engineering
*Nuclear physics
*Nuclear power
*Nuclear reactor
*Nuclear weapon
*Nuclear medicine
*Radiation therapy
*Nuclear warfare
Mathematics
*Nuclear space
*Nuclear ...
loci, indicate that a historic uplift event (800 – 1400 years before present) along the fault zone and subsequent recolonisation, has left a lasting impact upon the genetic diversity of the intertidal species ''
D. antarctica'' and ''
D. poha'', but not on the subtidal species ''
D. willana''.
Such a genetic impact may support the
founder takes all hypothesis.
Further genetic analysis has revealed that the population structure of two epifaunal species, the gribble ''
L. segnis'' and the chiton ''
O. neglectus'', closely matches the pattern observed in the intertidal host species of ''Durvillaea'' along the Akatore fault zone.
However, no matching pattern was observed for another epifaunal species, the amphipod ''
P. karaka'', most likely because this species has better swimming potential and can rely upon other host seaweeds.
Kaikōura
A substantial die off of ''Durvillaea'' bull kelp occurred along the
Kaikōura
Kaikōura () is a town on the east coast of the South Island of New Zealand. It is located on State Highway 1, 180 km north of Christchurch. The town has an estimated permanent resident population of (as of ).
The town is the government ...
coastline following the
2016 Kaikōura earthquake
The 2016 Kaikoura earthquake was a magnitude 7.8 (Mw) earthquake in the South Island of New Zealand that occurred two minutes after midnight on 14 November 2016 NZDT (11:02 on 13 November UTC). Ruptures occurred on multiple faults and the e ...
, which caused uplift up to 6 metres.
The loss of ''Durvillaea'' kelp caused
ecological disturbance
In ecology, a disturbance is a temporary change in environmental conditions that causes a pronounced change in an ecosystem. Disturbances often act quickly and with great effect, to alter the physical structure or arrangement of biotic and abiotic ...
, significantly affecting the biodiversity of the local intertidal community.
Aerial drone imaging two years after the earthquake indicated that ''Durvillaea'' abundance remained low on reefs with significant uplift, but it revealed offshore refuge populations less frequently detected by field researchers.
Areas Genetic analysis indicated that some of the ''Durvillaea'' that subsequently reached the affected coastline (i.e. potential colonists) came from areas >1,200 kilometres away.
Wellington and the Wairarapa
Based on genetic data, the predominantly southern-restricted species ''
D. poha'' appears to have undergone a recent
range expansion into the North Island, as it can be found at low frequencies along the Wellington coastline.
This range expansion coincides with areas affected by tectonic uplift and landslides caused by historic earthquakes, including the
1855 Wairarapa earthquake.
The removal of ''D. antarctica'' and formation of new coastline by such tectonic disturbance likely provided an ecological opportunity for ''D. poha'' to successfully colonise coastline north of the Cook Strait.
A genetic study of ''
D. antarctica'' identified distinct units of population structure across the uplift zone of the 1855 Wairarapa earthquake.
Notably, two spatial-genomic sectors of ''D. antarctica'' were identified on
Turakirae Head
Turakirae Head is a promontory on the southern coast of New Zealand's North Island. It is located at the western end of Palliser Bay, 20 kilometres southeast of Wellington, at the southern end of the Remutaka Range. The head is an excellent ex ...
, which received the greatest degree of uplift (2 – 6 m).
Phylogeographic modelling indicated that bull kelp that survived moderate uplift in the Wellington region (≤2 m) likely recolonised Turakirae Head via two parallel, eastward colonisation events - resulting in the two observed units of population structure.
The hierarchical phylogeographic variation observed in the study provided non-experimental evidence of
parapatric
In parapatric speciation, two subpopulations of a species evolve reproductive isolation from one another while continuing to exchange genes. This mode of speciation has three distinguishing characteristics: 1) mating occurs non-randomly, 2) gene ...
sectoring (see
Founder takes all) as a result of
natural disturbance, over a timescale observable to humans (i.e. <200 years).
It has been hypothesised that gaps in the current geographic range of ''
D. willana'' around Wellington and the Wairarapa may have been caused by local extinction following historic earthquake uplift events such as the 1855 Wairarapa earthquake.
However, uplift along the Akatore fault zone does not appear to have significantly affected the genetic diversity of ''D. willana'' in that region.
The interpretation of this genetic result for Akatore was that earthquake uplift is likely insufficient to cause the complete
extirpation
Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...
of subtidal kelp species such as ''D. willana''.
Species and distribution
There are currently eight recognised species within the genus, and the
type species
In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...
is ''D. antarctica''.
[Bory de Saint-Vincent, J.B.G.M. (1826). Laminaire, ''Laminaria''. In: ''Dictionnaire Classique d'Histoire Naturelle''. (Audouin, I. ''et al.'' Eds) Vol. 9, pp. 187-194.] All species are restricted to the Southern Hemisphere and many taxa are
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...
to particular coastlines or subantarctic islands.
* ''
Durvillaea amatheiae''
X.A. Weber, G.J. Edgar, S.C. Banks, J.M. Waters & C.I. Fraser, 2017,
[Weber, X.A., Edgar, G.J., Banks, S.C., Waters, J.M., and Fraser, C.I. "A morphological and phylogenetic investigation into divergence among sympatric Australian southern bull kelps (''Durvillaea potatorum'' and ''D. amatheiae'' sp. nov.)." Mol. Phylogenet. Evol. (2017) 107:630-643.] endemic to southeast Australia.
* ''
Durvillaea antarctica
''Durvillaea antarctica'', also known as ' and ', is a large, robust species of southern bull kelp found on the coasts of Chile, southern New Zealand, and Macquarie Island.Smith, J.M.B. and Bayliss-Smith, T.P. (1998). Kelp-plucking: coastal eros ...
''
(Chamisso
Adelbert von Chamisso (; 30 January 178121 August 1838) was a German poet and botanist, author of ''Peter Schlemihl'', a famous story about a man who sold his shadow. He was commonly known in French as Adelbert de Chamisso (or Chamissot) de Bonc ...
) Hariot,
found in New Zealand, Chile and various
subantarctic
The sub-Antarctic zone is a region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46° and 60° south of the Equator. The subantarctic region includes many islands ...
islands including
Macquarie Island
Macquarie Island is an island in the southwestern Pacific Ocean, about halfway between New Zealand and Antarctica. Regionally part of Oceania and politically a part of Tasmania, Australia, since 1900, it became a Tasmanian State Reserve in 197 ...
.
* ''
Durvillaea chathamensis''
C.H.Hay, 1979,
endemic to the
Chatham Islands
The Chatham Islands ( ) (Moriori: ''Rēkohu'', 'Misty Sun'; mi, Wharekauri) are an archipelago in the Pacific Ocean about east of New Zealand's South Island. They are administered as part of New Zealand. The archipelago consists of about te ...
.
* ''
Durvillaea fenestrata''
C. Hay, 2019,
endemic in the subantarctic
Antipodes Islands
The Antipodes Islands ( Maōri: Moutere Mahue; "Abandoned island") are inhospitable and uninhabited volcanic islands in subantarctic waters to the south of – and territorially part of – New Zealand. The 21 km2 archipelago lies 860  ...
.
* ''
Durvillaea incurvata''
( Suhr) Macaya,
endemic to Chile.
* ''
Durvillaea poha
''Durvillaea poha'' is a large, robust species of southern bull kelp found in New Zealand.
Discovery
The species was previously classified as the "cape" lineage of ''Durvillaea antarctica'', but in 2012 it was recognised as a distinct species ...
''
C.I. Fraser, H.G. Spencer & J.M. Waters, 2012,
endemic to South Island of New Zealand, as well as the subantarctic
Snares and
Auckland Islands
The Auckland Islands (Māori: ''Motu Maha'' "Many islands" or ''Maungahuka'' "Snowy mountains") are an archipelago of New Zealand, lying south of the South Island. The main Auckland Island, occupying , is surrounded by smaller Adams Island, ...
.
* ''
Durvillaea potatorum''
( Labillardière) Areschoug, endemic to southeast Australia.
* ''
Durvillaea willana
''Durvillaea willana'' is a large species of Durvillaea, southern bull kelp Endemism, endemic to New Zealand.
Etymology
The species epithet, ''willana'', honours Eileen Alice Willa who collected many algal species for Lindauer.
Description
This ...
''
Lindauer, 1949,
endemic to New Zealand.
Evolution
Time-calibrated
phylogenetic trees
A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spec ...
using mixtures of
mitochondrial and
nuclear DNA
Nuclear DNA (nDNA), or nuclear deoxyribonucleic acid, is the DNA contained within each cell nucleus of a eukaryotic organism. It encodes for the majority of the genome in eukaryotes, with mitochondrial DNA and plastid DNA coding for the rest. I ...
markers have estimated that ''Durvillaea'' diverged from other brown algae approximately 20 to 60 million years ago.
Given the modern distribution of extant ''Durvillaea'' species throughout the Southern Ocean, it has been suggested that the distribution may reflect
vicariance
Allopatric speciation () – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from ...
following the break-up of
Gondwana
Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages ...
40 to 50 million years ago, but this distribution can also be explained by the long-distance dispersal of buoyant ''Durvillaea'' lineages throughout the Southern Ocean.
Based on molecular phylogenetic research, non-buoyancy is not necessarily the
ancestral state
In phylogenetics, a primitive (or ancestral) character, trait, or feature of a lineage or taxon is one that is inherited from the common ancestor of a clade (or clade group) and has undergone little change since. Conversely, a trait that appears ...
for the genus,
and non-buoyant lineages could have still been transported across the ocean when attached to rafts of different species of buoyant algae.
A phylogeny focused on the genus, based on four genes (
COI,
rbcL
Ribulose-1,5-bisphosphate carboxylase-oxygenase, commonly known by the abbreviations RuBisCo, rubisco, RuBPCase, or RuBPco, is an enzyme () involved in the first major step of carbon fixation, a process by which atmospheric carbon dioxide is con ...
,
28S
28S ribosomal RNA is the structural ribosomal RNA (rRNA) for the LSU rRNA, large subunit (LSU) of eukaryotic cytoplasmic ribosomes, and thus one of the basic components of all eukaryotic cells. It has a size of 25S in plants and 28S in mammals, ...
and
18S) indicates the evolutionary relationships shown in the cladogram below.
Notably, additional unclassified lineages were estimated within ''D. antarctica''.
Mitochondrial
introgression
Introgression, also known as introgressive hybridization, in genetics is the transfer of genetic material from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species. Intr ...
has been observed between two species, where some individuals with nuclear DNA of ''D. poha'' exhibited mitochondrial DNA belonging to ''D. antarctica''.
Use of ''Durvillaea'' species
Australia
''
D. potatorum'' was used extensively for clothing and tools by
Aboriginal Tasmanians
The Aboriginal Tasmanians (Palawa kani: ''Palawa'' or ''Pakana'') are the Aboriginal people of the Australian island of Tasmania, located south of the mainland. For much of the 20th century, the Tasmanian Aboriginal people were widely, and ...
, with uses including material for shoes and bags to transport freshwater and food.
Currently, ''D. potatorum'' is collected as beach
wrack from
King Island, where it is then dried as chips and sent to
Scotland
Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the ...
for