The evolutionary origin of a second radiation of annual Castilleja
 (Orobanchaceae) species in South America: The role of long distance dispersal and allopolyploidy

AbstractSamples from 73 pieces of non-structural driftwood on Heard Island (53°06′S, 73°30′E) were identified to genus or species. Thirty-one belonged to South American species of Nothofagus. The remainder, consisting mostly of conifers especially Picea and Larix, probably came from ships' cargoes. The assemblage is similar to those reported, from smaller samples, on other southern islands. Other items of flotsam, including fishing buoys and drift-cards, are also reported from Heard Island. The significance of driftwood transport from South America to the island in accounting for long-distance dispersal of terrestrial and intertidal organisms is discussed.

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The role of mucilage envelope in the endozoochory of selected plant taxa

The Science of Nature ◽

10.1007/s00114-020-01709-7 ◽

2020 ◽

Vol 108 (1) ◽

Author(s):

A. Kreitschitz ◽

E. Haase ◽

S. N. Gorb

Keyword(s):

Digestive System ◽

Columba Livia ◽

Local Scale ◽

Ocimum Basilicum ◽

Long Distance Dispersal ◽

Morphological Adaptation ◽

Long Distance ◽

Germination Ability ◽

First Time

AbstractMyxodiaspory (formation of mucilage envelope around seeds and fruits) is a common adaptation to dry habitats known in many families of Angiosperms. The mucilage envelope of some seeds seems to be also a unique morphological adaptation which protects myxospermatic diaspores while passing through the bird’s digestive system. To evaluate the protective potential of mucilage, we fed the diaspores of seven plant species (representing three different mucilage types and three species of non-mucilaginous plants) to pigeons, Columba livia domestica. Twenty-four hours later, we collected the droppings of pigeons and examined a total of 18,900 non-destroyed diaspores to check for mucilage presence and germination ability. Out of all the examined diaspores, 4.5% were mucilaginous seeds. Among them, the highest number (12.2–13.5%) of viable diaspores belonged to the hemicellulosic type of mucilage (from Plantago species). Only 3.7% of germinating diaspores with pectic mucilage (Linum usitatissimum) were collected, and no seeds representing cellulosic mucilage (e.g., Ocimum basilicum). For non-mucilaginous plants, we collected only a few individual seeds (0.1% out of 8100 seeds used). We noted that the mucilaginous seeds found in the droppings were able to germinate; however, the germination ability was generally smaller in comparison to the control (i.e., not digested) seeds. Our results revealed that the presence of mucilage envelope has an impact on diaspore dispersal and survivability. With our experiments, we demonstrated for the first time that the mucilage envelope, especially of the non-cellulosic type, supports endozoochory. We also showed that non-mucilaginous seeds can be occasionally dispersed via endozoochory and are able to germinate. The results of our studies can explain the ways of plants distribution at a small, local scale as well as in long-distance dispersal, e.g., between islands or even continents.

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Influence of gut morphology on passive transport of freshwater bryozoans by waterfowl in Doñana (southwestern Spain)

Canadian Journal of Zoology ◽

10.1139/z04-055 ◽

2004 ◽

Vol 82 (6) ◽

pp. 835-840 ◽

Cited By ~ 24

Author(s):

Jordi Figuerola ◽

Andy J Green ◽

Katrina Black ◽

Beth Okamura

Keyword(s):

Aquatic Invertebrates ◽

Bird Species ◽

Passage Time ◽

Passive Dispersal ◽

Long Distance Dispersal ◽

Long Distance ◽

Active Dispersal ◽

Intestine Length ◽

Internal Transport

Waterbirds have been proposed as important vectors for the passive dispersal of those aquatic invertebrates and plants that lack a capacity for active dispersal between isolated water bodies. We analysed the frequency of internal transport of bryozoan propagules (statoblasts) by waterbirds in Doñana, Spain, by examining their presence in the intestines and ceca of dead birds and analysing the role of different aspects of gut characteristics in explaining variation in the presence/absence and abundance of statoblasts. Of the 228 samples examined, 7.9% presented intact statoblasts of Plumatella fungosa (Pallas, 1768), Plumatella emarginata Allman, 1844, and two unidentified Plumatella species. For a given bird species, individuals with heavier gizzards and shorter ceca had a lower incidence and abundance of statoblasts in the lower gut. Grit mass and intestine length were unrelated to the presence or abundance of statoblasts. Our results suggest that waterbirds frequently transport bryozoans on a local scale, with lighter gizzards and longer ceca favouring such transport. Lighter gizzards are likely to destroy fewer propagules before they reach the lower gut. Species and individuals with longer ceca are particularly good candidates for long-distance dispersal of bryozoans, given the longer passage time of propagules that enter the ceca.

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Predicting Plant Migration Rates in a Changing World: The Role of Long-Distance Dispersal

The American Naturalist ◽

10.2307/2463662 ◽

1999 ◽

Vol 153 (5) ◽

pp. 464 ◽

Cited By ~ 1

Author(s):

Higgins ◽

Richardson

Keyword(s):

Long Distance Dispersal ◽

Long Distance ◽

Plant Migration ◽

Migration Rates ◽

Changing World

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Floristics of the South American Páramo Moss Flora

Bryophyte Diversity and Evolution ◽

10.11646/bde.2.1.10 ◽

1990 ◽

Vol 2 (1) ◽

pp. 127-132

Author(s):

Dana Griffin III

Keyword(s):

South America ◽

Southern Hemisphere ◽

Cloud Forest ◽

South American ◽

Long Distance Dispersal ◽

The South ◽

Long Distance ◽

Late Pliocene ◽

Northern Andes ◽

The Past

The South American paramos appeared in Pliocene times and persist to the present day. The moss flora of this habitat consists of an estimated 400 species that comprise 8 floristic groups. In Venezuela these groups and their percent representation are as follows: neotropical 37%, Andean 26%, cosmopolitan 18%, Andean-African 8%, neotropical-Asiatic 3%, neotropical-Australasian 2%, temperate Southern Hemisphere 2% and northern boreal-temperate 2%. Acrocarpous taxa outnumber pleurocarps by nearly 3:1. The neotropical and Andean floristic stocks likely were present prior to late Pliocene orogenies that elevated the cordillera above climatic timberlines. These species may have existed in open, marshy areas (paramillos) or may have evolved from cloud forest ancestors. Taxa of northern boreal- temperate affinities, including those with Asiatic distributions, probably arrived in the paramos during the Pleistocene, a period which may also have seen the establishment in the Northern Andes of some cosmopolitan elements. Species with temperate Southern Hemisphere and Australasian affinities likely spread first to austral South America thence migrated northward during a cool, moist interval sometime over the past 2.5-3 million years or may have become established in the paramos as a result of long- distance dispersal.

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Evidence of avian-mediated long distance dispersal in American tardigrades

PeerJ ◽

10.7717/peerj.5035 ◽

2018 ◽

Vol 6 ◽

pp. e5035 ◽

Cited By ~ 10

Author(s):

Matthew J. Mogle ◽

Scott A. Kimball ◽

William R. Miller ◽

Richard D. McKown

Keyword(s):

Bird Species ◽

Distribution Patterns ◽

Long Distance Dispersal ◽

Long Distance ◽

Neotropical Migrant ◽

Grus Canadensis ◽

Sandhill Crane ◽

Migrant Birds ◽

North And South

Terrestrial tardigrades, commonly known as “water bears”, are part of a phylum of microscopic, aquatic invertebrates famous for cryptobiosis and space travel, but little is known about their modes of dispersal on Earth. Wind is assumed, but not truly demonstrated, to be the major method of global dispersal. Yet, some water bear distribution patterns cannot be explained by patterns of prevailing winds. Mammals and birds have been proposed as potential animal vectors. Importantly, most nearctic-neotropical migrant birds move north and south, with many crossing the equator, whereas prevailing winds move west to east or east to west but do not cross the equator. When multiplied by billions of birds over tens of millions of years, if the ectozoochory of tardigrades by birds is true then both regional and intercontinental patterns can be better explained. To test for the potential role of birds in tardigrade dispersal, the nests of 10 species for birds were examined. Seventy percent of nests were positive for tardigrades, demonstrating that some birds are in a position for transference. The carcasses of eight birds (six species) found dead from window strikes and a Sandhill Crane (Grus canadensis) found dead during routine surveys were also examined. Of the birds examined, 66% yielded tardigrades from two classes, three orders, and five species, including juveniles, adults, and eggs, suggesting that many bird species are potential vectors for many species of tardigrades. Our data support the hypothesis of avian-mediated long distance dispersal of tardigrades and provide evidence that further investigation is warranted.

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