Monday 30 November 2020

Time Management Tips for Entomology Graduate Students | Entomology Today

This post Time Management Tips for Entomology Graduate Students appeared first on Entomology Today - Brought to you by the Entomological Society of America.

Feeling rushed? The demands of pursuing a graduate degree can be daunting. Check out these tips and suggestions for optimizing time management—and reducing stress—for graduate students in entomology and related areas of study.

The post Time Management Tips for Entomology Graduate Students appeared first on Entomology Today.

The Spread of Carrots

Carrots are one of the staple vegetables in this part of the world as well as in a great many others. Indeed, Wikipedia informs us that about forty million tonnes of carrots and turnips were produced worldwide in 2018, and I would have to think that carrots accounted for the greater part of that number. Wild carrots are also a widespread weed that can commonly be seen growing in disturbed, open habitats such as roadside verges. This post is about the group of plants that carrots typify, the subtribe Daucinae.

Wild carrot Daucus carota in flower, copyright Cwmhiraeth.


Daucinae is a subgroup of the plant family Apiaceae, historically known as the Umbelliferae. The latter name refers to the characteristic production of flowers in dense, flat-topped inflorescences known as umbels. Anyone who is familiar with the appearance of carrot flower-heads is familiar with the form of an umbel; the wild form of carrot is often known as "Queen Anne's lace" in reference to said appearance. The fruit of Apiaceae species is a schizocarp, a dry fruit that splits at maturity into segments (called mericarps), each containing a single seed, that are dispersed independently. In Daucinae and related group of umbellifers, the mericarps carry longitudinal ribs, both primary ribs containing a vascular bundle and secondary ribs without. The secondary ribs of Daucinae are often modified to form broad wings or curved spines that function in the mericarp's dispersal.

Broad-leafed sermountain Laserpitium latifolium seedheads, showing wings, copyright Krzysztof Ziarnek, Kenraiz.


Historically, these differences in mericarp morphology have been used to assign the species bearing them to different tribes. However, more recent phylogenetic analyses have indicated that changes between wings and spines have occurred on multiple occasions due to changes in mode of dispersal (Wojewódzka et al. 2019). Mericarps bearing wings are generally anemochorous (dispersed by wind) whereas those bearing spines are epizoochorous (carried by animals, such as stuck to a mammal's fur). The distinction is not 100% immutable: winged seeds may sometimes get caught in fur, spined seeds may be carried slightly further by wind than smooth ones. Phylogenies indicate that anemochory was the ancestral condition for Daucinae, retained in genera such as Laserpitium and Thapsia. Epizoochorous species do not form a single clade within the Daucinae (indeed, the genus Daucus includes both anemochorous and epizoochorous species) but it is unclear to what degree epizoochory arose on multiple occasions versus reversions to anemochory from epizoochorous ancestors. Two species of Daucinae, Daucus dellacellae from the Cyrenaica region of northern Africa and Cryptotaenia elegans from the Canary Islands, have neither spines nor wings on their mericarps which are therefore dispersed by gravity alone. In the case of C. elegans, at least, it has been suggested that it evolved from epizoochorous ancestors that lost the spines because of the absence of suitable dispersing animals on the islands (Banasiak et al. 2016).

Though the carrot Daucus carota is perhaps the most widely grown daucine umbellifer, it is not the only economically significant member of the group. Cumin Cuminum cyminum, whose seeds are widely used as a spice, is either a daucine or a close relative of daucines (Banasiak et al. 2016). Cuminum does differ from other daucine genera in that its mericarps lack appendages on the secondary keels, however. Gladich Laser trilobum is a perennial found growing in Europe and western Asia whose seeds are used as a condiment. Certain species of the deadly carrot genus Thapsia have a history of medicinal usage though, as their vernacular name suggests, their use does require caution. One species, T. garganica, is among the suggested candidates for the identity of the mysterious silphium of the Romans (used, among other things, as an abortifacient) though perhaps not the most likely contender. That, perhaps, is a story for another time.

REFERENCES

Banasiak, Ł., A. Wojewódzka, J. Baczyński, J.-P. Reduron, M. Piwczyński, R. Kurzyna-Młynik, R. Gutaker, A. Czarnocka-Ciecura, S. Kosmala-Grzechnik & K. Spalik. 2016. Phylogeny of Apiaceae subtribe Daucinae and the taxonomic delineation of its genera. Taxon 65 (3): 563–585.

Wojewódzka, A., J. Baczyński, Ł. Banasiak, S. R. Downie, A. Czarnocka-Ciecura, M. Gierek, K. Frankiewicz & K. Spalik. 2019. Evolutionary shifts in fruit dispersal syndromes in Apiaceae tribe Scandiceae. Plant Systematics and Evolution 305: 401–414.

source http://coo.fieldofscience.com/2020/11/the-spread-of-carrots.html

Tuesday 24 November 2020

How Ants’ Individual Encounters Influence Colony-Wide Behavior, and Vice Versa | Entomology Today

This post How Ants’ Individual Encounters Influence Colony-Wide Behavior, and Vice Versa appeared first on Entomology Today - Brought to you by the Entomological Society of America.

A new review of ant research illuminates how ant behavior is driven by a cascade of individual decisions among colony members. Insights on ant movement and encounter rates also suggest parallels to collective behavior in another population under the microscope in 2020: humans.

The post How Ants’ Individual Encounters Influence Colony-Wide Behavior, and Vice Versa appeared first on Entomology Today.

Monday 23 November 2020

Frantic About Residential Tick Management? This Film Series is Just for You | Entomology Today

This post Frantic About Residential Tick Management? This Film Series is Just for You appeared first on Entomology Today - Brought to you by the Entomological Society of America.

Tick researchers in Connecticut turn their eye toward their local community with an educational film series about backyard tick management. Learn how the project came together and why it could be a useful model for other entomology-outreach efforts.

The post Frantic About Residential Tick Management? This Film Series is Just for You appeared first on Entomology Today.

Saturday 21 November 2020

Silicon Rockets

In a previous post, I spoke of the radiolarians, marine protists renowned for their intricate skeletons, and the major radiolarian group known as the Spumellaria. Standing in contrast to the spumellarians is another major group, the Nassellaria. Like spumellarians, nassellarians have a skeleton of silica but whereas the basic shape of spumellarian skeleton is a sphere, that of nassellarians is a cone, bell or some similar shape, arranged along a longitudinal axis. The origination point of the skeleton is at or near the top of the cone and is known as the cephalis (from the Greek for 'head'). There may be an apical spine rising above the cephalis. Below it, the skeleton is commonly divided into recognisable sections referred to as the thorax, abdomen and post-abdominal segments (if present). The nucleus of the cell is more or less associated with the cephalis, contained within it at least during the juvenile stage of development though it may shift below the cephalis as the cell matures (Suzuki et al. 2009).

Skeleton of a Eucyrtidium sp., copyright Picturepest.


As is commonly the case with unicellular organisms, radiolarian taxonomy has been influenced by disagreements about which features should be regarded as more significant. Some would arrange taxa based on the overal formation of the skeleton. Others would focus on the development of the initial embryonic spicule around which the cephalis develops. A recent phylogenetic analysis of living nassellarians by Sandin et al. (2019), based on both morphological and molecular data, found that overall skeleton morphology was a much better indication of relationships than the internal structure. One well supported subgroup of the Nassellaria is the superfamily Eucyrtidioidea.

Eucyrtidioids have a fossil record going back to the Triassic (Afanasieva et al. 2005). The cephalis is spherical and clearly distinguished from the following segments by a constricted basal aperture. The test is usually multi-segmented; members of the subfamily Theocotylinae may have just two segments but other members of Eucyrtidiidae have up to ten segments. Fossil families assigned to Eucyrtidioidea by Afanasieva et al. (2005) may have up to twenty (but as Afanasieva et al.'s concept of Eucyrtidioidea was not found to be monophyletic by Sandin et al., the affinities of these fossil families perhaps warrant re-investigation). Segments are commonly divided by distinct inner rings. The skeleton lacks feet, the term used for protruding spines around the basal aperture of the skeleton found in many other nassellarians.

The phylogeny of nassellarians indicated by Sandin et al. (2019) places the Eucyrtidiidae as the sister taxon to other living nassellarians. Other living families included in the Eucyrtidioidea by Afanasieva et al. (2005) were placed in more nested positions. The implication is that the multi-segmented condition may be ancestral for crown Nassellaria. Segments are added progressively during the life of the radiolarian, leading the organism to look quite different at different ages. Indeed, this metamorphosis is pronounced enough that one of the earliest influential researchers on radiolarians, Ernst Haeckel (he of Kunstformen der Natur fame), made the mistake of classifying different ages as different species, genera and even families. Our understanding may be better than in Haeckel's time but there may still be a lot to learn about these intricate organisms.

REFERENCES

Afanasieva, M. S., E. O. Amon, Y. V. Agarkov & D. S. Boltovskoy. 2005. Radiolarians in the geological record. Paleontological Journal 39 (Suppl. 3): S135–S392.

Sandin, M. M., L. Pillet, T. Biard, C. Poirier, E. Bigeard, S. Romac, N. Suzuki & F. Not. 2019. Time calibrated morpho-molecular classification of Nassellaria (Radiolaria). Protist 170: 187–208.

Suzuki, N., K. Ogane, Y. Aita, M. Kato, S. Sakai, T. Kurihara, A. Matsuoka, S. Ohtsuka, A. Go, K. Nakaguchi, S. Yamaguchi, T. Takahashi & A. Tuji. 2009. Distribution patterns of the radiolarian nuclei and symbionts using DAPI-fluorescence. Bulletin of the National Museum of Nature and Science, Series B 35 (4): 169–182.

source http://coo.fieldofscience.com/2020/11/silicon-rockets.html

Friday 20 November 2020

Entomology 2020: Attendees Note Favorites From Live Sessions | Entomology Today

This post Entomology 2020: Attendees Note Favorites From Live Sessions appeared first on Entomology Today - Brought to you by the Entomological Society of America.

Entomology 2020 continued this week, with four days of live symposia and programming taking place Monday through Thursday. Once again, Entomology Today asked participants to share some of their favorites from the live events, plus more on-demand content they may have watched. Find out what has #EntSoc20 participants buzzing!

The post Entomology 2020: Attendees Note Favorites From Live Sessions appeared first on Entomology Today.

Wednesday 18 November 2020

Diminutive Dragonfly Makes New Appearance in Michigan | Entomology Today

This post Diminutive Dragonfly Makes New Appearance in Michigan appeared first on Entomology Today - Brought to you by the Entomological Society of America.

Ophiogomphus howei, the smallest dragonfly of its genus and known to inhabit ranges primarily in Appalachia and Wisconsin in the United States, has been discovered by Odonata enthusiasts in southern Michigan, in a setting that may prompt a rethink of the species' habitat preferences.

The post Diminutive Dragonfly Makes New Appearance in Michigan appeared first on Entomology Today.

Tuesday 17 November 2020

Shut the Front Door! Researchers Find ‘Endangered Living Fossil’ Trapdoor Spider | Entomology Today

This post Shut the Front Door! Researchers Find ‘Endangered Living Fossil’ Trapdoor Spider appeared first on Entomology Today - Brought to you by the Entomological Society of America.

Meet Cryptocteniza kawtak, a newly described genus and species of trapdoor spider that likely dates to the Cretaceous. The researcher who found it first spotted it in 1997 but was finally able to enter it in the scientific record after finding another specimen two decades later.  

The post Shut the Front Door! Researchers Find ‘Endangered Living Fossil’ Trapdoor Spider appeared first on Entomology Today.

Friday 13 November 2020

Entomology 2020: Attendees Share Early Reactions to On-Demand Presentations, Posters | Entomology Today

This post Entomology 2020: Attendees Share Early Reactions to On-Demand Presentations, Posters appeared first on Entomology Today - Brought to you by the Entomological Society of America.

Entomology 2020 began Wednesday, and Entomology Today asked some participants to share some of their favorite symposia, presentations, and posters they've seen thus far. Get a glimpse into the wealth of knowledge available at the ESA Virtual Annual Meeting, happening now through November 25.

The post Entomology 2020: Attendees Share Early Reactions to On-Demand Presentations, Posters appeared first on Entomology Today.

Thursday 12 November 2020

Vector-Borne Disease: CDC Report Outlines Key Steps for Prevention and Control in U.S. | Entomology Today

This post Vector-Borne Disease: CDC Report Outlines Key Steps for Prevention and Control in U.S. appeared first on Entomology Today - Brought to you by the Entomological Society of America.

Perhaps overlooked in the public eye upon its release in September, a new "framework" report from the U.S. Centers for Disease Control and Prevention is none the less a vital step forward in the nation's efforts to better support and coordinate the prevention and control of vector-borne diseases. Here's a closer look at the report and what's next in this critical public-health pursuit.

The post Vector-Borne Disease: CDC Report Outlines Key Steps for Prevention and Control in U.S. appeared first on Entomology Today.

Tuesday 10 November 2020

Plum Curculio: New Guide Gathers IPM Recommendations for North American Fruit Pest | Entomology Today

This post Plum Curculio: New Guide Gathers IPM Recommendations for North American Fruit Pest appeared first on Entomology Today - Brought to you by the Entomological Society of America.

The plum curculio has a long history as a pest of fruit in North America, but it has gone somewhat understudied. A new article in the open-access Journal of Integrated Pest Management reviews the plum curculio’s biology, life history, and behavior and IPM options for growers.

The post Plum Curculio: New Guide Gathers IPM Recommendations for North American Fruit Pest appeared first on Entomology Today.

Monday 9 November 2020

A New Guide for Tick Researchers on Working With Mice | Entomology Today

This post A New Guide for Tick Researchers on Working With Mice appeared first on Entomology Today - Brought to you by the Entomological Society of America.

Entomologists studying ticks and the disease pathogens they carry must also become adept at handling the host animals that ticks feed on, such as mice. A new article in the open-access Journal of Insect Science offers a guide to do just that, part of a new special collection on protocols in medical and veterinary entomology.

The post A New Guide for Tick Researchers on Working With Mice appeared first on Entomology Today.

Thursday 5 November 2020

Even Moderate Drought Conditions are Bad for Bees | Entomology Today

This post Even Moderate Drought Conditions are Bad for Bees appeared first on Entomology Today - Brought to you by the Entomological Society of America.

A new study finds that reduced water availability—even if not quite drought conditions—lessens the quality of floral resources for honey bees and bumble bees, in turn negatively affecting their survival and reproduction rates.

The post Even Moderate Drought Conditions are Bad for Bees appeared first on Entomology Today.

Wednesday 4 November 2020

Residential Pest Management: What Do Homeowners Know, and What Do They Do? | Entomology Today

This post Residential Pest Management: What Do Homeowners Know, and What Do They Do? appeared first on Entomology Today - Brought to you by the Entomological Society of America.

Massive quantities of pesticides are applied by homeowners on residential lawns and gardens each year. While some have an understanding of integrated pest management concepts and practice them on their property, many do not and indiscriminately apply pesticides. There is an opportunity for cooperative extension personnel to address this need by providing residential IPM and pesticide education programs.

The post Residential Pest Management: What Do Homeowners Know, and What Do They Do? appeared first on Entomology Today.

Sunday 1 November 2020

Tricolia: Fluorescent Seashells

Tricolia pullus, copyright Ar rouz.


Search among patches of seaweed along the shores of Africa, Australia or warmer parts of Eurasia and you may be able to find represents of the marine gastropod genus Tricolia. Tricolia are small shells, less than a centimetre in height, with shiny shells that may be smooth or spirally ribbed. Most species have a moderately high spire and an ovate shape but some are lower and more globose (Knight et al. 1960). The shell may or may not have an umbilicus, and there is a calcareous, externally convex operculum. Tricolia belongs to the Phasianellidae, commonly known as pheasant shells, presumably in reference to the bold, intricate colour patterns of many species. Species of Tricolia and the closely related genus Eulithidium, which replaces it in the Americas, have shell pigments containing porphyrin that fluoresce under ultraviolet light (Vafiadis & Burn 2020). Over forty species of Tricolia are currently recognised with the highest diversity in southern Africa (Nangammbi et al. 2016). However, the taxonomy of the genus has historically been confused due to polymorphic species being named multiple times; it is possible that at least some of the apparent African diversity is an artefact of the genus being largely unrevised in that region. An analysis of some of the southern African taxa by Nangammbi et al. (2016) found that some 'species' could not be distinguished genetically. They were, nevertheless, distinct geographically and the authors suggested that they may be variants of a single species responding to different environments.

Variants of Tricolia kochii, copyright Brian du Preez.


Like other members of the Vetigastropoda (the clade containing most of what used to be called the 'archaeogastropods'), Tricolia species have a simple life cycle without an actively feeding planktonic larva. The basic mode of reproduction is by broadcast spawning with separate males and females releasing gametes into the water column. After fertilisation, a brief non-feeding planktonic phase is nourished by yolk from the egg before the larva settles. The brevity of this phase is reflected by the resultant form of the protoconch which accounts for less than an entire whorl. In the Indo-West Pacific species T. variabilis, the male is smaller than the female and sits directly on her, waiting to fertilise her eggs as they are laid as gelatinous capsules rather than freely broadcasted. A temperate Australian species, T. rosea, takes things a step further as the female broods embryos (up to nearly fifty at a time) within the cavity of the last shell whorl (Vafiadis & Burn 2020). How the eggs are actually fertilised remains unknown but all embryos within a brood are about the samesize and stage of development, indicating a single fertilisation event; perhaps males associate with females as in T. variabilis. After the young pheasant shells hatch or settle, they initially feed on diatoms and other microalgae until they eventually grow enough to move onto the seaweed fronds that will comprise their adult diet.

REFERENCES

Knight, J. B., L. R. Cox, A. M. Keen, R. L. Batten, E. L. Yochelson & R. Robertson. 1960. Gastropoda: systematic descriptions. In: R. C. Moore (ed.) Treatise on Invertebrate Paleontology pt I. Mollusca 1. Mollusca—general features, Scaphopoda, Amphineura, Monoplacophora, Gastropoda—general features, Archaeogastropoda and some (mainly Paleozoic) Caenogastropoda and Opisthobranchia pp. I171–I351. Geological Society of America: Boulder (Colorado), and University of Kansas Press: Lawrence (Kansas).

Nangammbi, T. C., D. G. Herbert & P. R. Teske. 2016. Molecular insights into species recognition within southern Africa's endemic Tricolia radiation (Vetigastropoda: Phasianellidae). Journal of Molluscan Studies 82: 97–103.

Vafiadis, P., & R. Burn. 2020. Internal embryonic brooding and development in the southern Australian micro-snail Tricolia rosea (Angas, 1867) (Vetigastropoda: Phasianellidae: Tricoliinae). Molluscan Research 40 (1): 60–76.

source http://coo.fieldofscience.com/2020/11/tricolia-fluorescent-seashells.html