Speck of Science 12/1/16 – How Elephants Are Losing Their Tusks

tusklesselephants_billgordon
Small-tusked elephant, source: African Wildlife Foundation

Nature has a fickle way of removing the wheat from the chaff. When organisms are less suited to survival, their chances of lasting long enough to reproduce may be in serious jeopardy. If the deleterious traits are genetic in nature, then there is limited chance they will be handed off to future generations. We call this process natural selection.

One example proving that humans can act as a shaping force similar to mother nature by chiseling the genetic outlook  of a creature is presented in this recent Independent article.The piece describes how African elephants in some regions are being born with smaller tusks or entirely without them, presumably in response to the selective pressure of poaching. While there always have been an elephant here or there born without tusks, the preferential culling of ivory has increased the prevalence of tuskless elephants.

african-elephants-ivory-tusks-615
Photo credit: National Geographic

However, as Snopes suggests (not a source I was expecting to comment on the issue), this particular phenomenon has been noted and written about for years prior. A 1995 paper published in the African Journal of Ecology noted in Queen Elizabeth National Park had jumped from 3-4% up to 9-25%. Collectively in South Luangwa National Park and nearby Lupande Game Management Area, the change was from 10% up to 38% in a 20 year period.

While elephants may be the charismatic mascot for poaching issues, undoubtedly it is an issue that for a multitude of animal species reverberates well beyond just their population size and deeply into the very tapestry of their DNA.

Advertisements

Speck of Science 11/29/16 – The Bathing of the Tortoise

jonathan-the-tortoise-1900
A photo of Jonathan dated at around 1886 – Wikimedia Commons

Jonathan, a 184 year old tortoise touted as perhaps the oldest living land animal, seemed a little surprised at times in this video released by the St. Helena government.

The solid scrubbing appeared to be an attempt to renew the vim and vigour of his shell, as Joe Hollins, the vet who did the deed stated: “It is purely for aesthetic reasons.  We want visitors and tourists on the Island to witness the tortoises in their true form, without the obstruction of moss and lichen on their shells.  There is so much interest in Jonathan, St Helena’s most famous animal resident, and we want all who visit him to see him at his best.”

In recent years, Hollins also oversaw an overhaul of Jonathan’s diet, which seems to have increased his overall well being. Sounds like Jonathan has a pretty savvy ally and friend.

 

Speck of Science 8/17/16 – The Greenland Shark abides

6376473_orig
Source: Ocean Treasures Memorial Library

Several news outlets this week have justifiably made a big deal about the Greenland Shark. Recent research suggests these lumbering giants are now the record holder for the longest lived vertebrates we are aware of. This knocks the Bowhead whale from first place, whose age-determination story is fascinating in its own right, bolstered by the presence of an antique eskimo harpoon point.

Often sharks have been aged through examining growth bands present in vertebrae, however Greenland sharks have softer vertebrae that make this challenging. Additionally, due to challenges in reading these rings as sharks age, as well as possible disconnects between growth rate and age, radiocarbon dating has been joining the toolbox for determining fish longevity.  This study used the method with the sharks’ eye lenses.

greenland_shark_parasite

These sharks may take up to 150 years to reach sexual maturity, making their population vulnerable if too many individuals are culled before reproducing. They are also bizarrely prone to parasitism by a strangely-elongate copepod (most look more shrimp or lobster-like) that attaches to their eyeball and ultimately causes a march towards blindness. Only 1% of the 1500 sharks in a study concerning infection rates were parasite-free. 85% are afflicted in both eyes. However, due to their reliance on a keen sense of smell, rather than sight, for hunting, it has been suggested that the sharks may actually benefit from the copepod acting as small visible lures that interest nearby prey. However, Dr. George Benz of Middle Tennessee State University with expertise in shark and ray parasites, doubts this theory, instead favoring the idea that Greenland sharks may instead be ambush hunters, taking their targets instead through the element of surprise.

Speck of Science 8/15/16 – Nat Geo Writes About Pooping Comb Jellies

maxresdefault
Still from Ryan M. Bolton 2016 video: https://www.youtube.com/watch?v=weeFO6kLu5o

Lest you think National Geographic is losing their edge, the reason why ctenophores (the phylum to which comb jellies belong) defecating is a big deal is because it was thought this group of creatures had a single opening for both feeding and excreting. University of Miami researcher William Brown debuted videos at the March 2016 Ctenopolooza gathering at the Whitney Lab in St. Augustine (where I’ve done much of my own dissertation field and lab work) that prove otherwise. One of the peculiar videos is featured partway through Nat Geo’s article here. Science writes about the find as well.

One of the most interesting aspects of this find is questions regarding the evolutionary history of gut development. It was thought to be a pretty straight forward pathway from one opening to two. However, because comb jellies evolved before other organisms that still have a single opening, such as sponges, things are looking slightly more interesting. Perhaps ctenophores branched off, and smartly evolved a more complex gut tract independent of these organisms. Or, perhaps some of these single-orificed organisms started with two but lost one over time – similar to the story of some marine mammals that long ago left the sea to become land-dwellers, only to ultimately return again.

 

 

Speck of Science – 4/19/16 – March of the Crabs

christmas-island-red-crab
Source: Animal Planet

Mass migrations fascinate me – massive swarms of creatures on robotic treks to satisfy deep-seated needs for resources – nature’s automatons reaching for food, for mates, for brighter skies. One of the earliest that captured my attention is expressed in this Animal Planet video documenting the movement of red crabs on Christmas Island:

http://www.animalplanet.com/tv-shows/wild-kingdom/videos/christmas-island-red-crabs/

(Note at 1:40, crustaceans seem to be playing “frogger” while obliviously scuttling across roads and railroad tracks. Not the unexpected result of the clash between crab and human.)

A gif of the oceanic equivalent has made a recent appearance online, showing an endless carpet of sandy colored scuttlers (they were in fact red,  or “tuna,” crabs who appeared that way as they stirred up a the sediment on the sea floor). However, this article sheds more light on the unusual event captured by a manned submersible exploring Hannibal Bank off of Panama (fitting name for the location of a slightly unnerving and intriguing event to occur? ). The following video comes from Woods Hole Oceanographic Institut and features scientist Jesús Pineda explaining the details around recording the migration:

 

 

Speck of Science – 4/6/2016 – Gimme Back My Buoy

I have been through a blogging dry spell lately, but nothing like starting out again with the amusing news of 2 men essentially holding a USGS (United States Geological Survey) scientific buoy hostage.

cce-map
A Map of the Monterey Bay Aquarium Research Institute’s Coordinated Canyon Experiment. The buoy was associated with this particular project. Source: MBARI

The buoy, which was deployed to gather data related to El Niño events, drifted off its mooring during a recent storm. Two fishermen chanced upon it, recovered it, and are now demanding $13,000 in exchange for its return. Their lawyer, a seemingly rather colorful character and self-described “old trial dog”, initially set the price a bit higher based on the following mathematics: ” On good days fishing they gross $2,700. Taking the big and gouging thing onto the boat and having it there kept the boat out of action for nine days for a multiply of $24,300. Twenty percent of value would be $80,000. We offer to SELL (you can use any other word you like in an agreement) it to you for $45,000.” One has to wonder why they took it upon themselves to keep the “big and gouging thing” on their boat for nine days in the first place.

The article notes from several sources that salvage laws likely do not apply here, especially as the buoy was never properly abandoned. However, the loss of and tampering with of expensive research equipment has always been a known and pervasive issue in oceanic research.  I for one will be interested to follow the outcome of this eyebrow-raising case.

5 Examples of the Revolution of 3D Printing in the Sciences

Here is a quick list re-visiting some of the more innovative and thought-provoking applications or ideas surrounding 3D printing in the sciences over the past few years:

1-intro
Credit: Wake Forest Medical Center
  • Printing human tissue. Recent news shows we’re able to use 3D printing more effectively to create intricate models of organs for learning purposes. However, a smattering of experts across disciplines have made progress in printing processes that utilize the stuff of the human body to create swaths of tissue that can be used for grafts or testing. The purported next step is the more complex arrangement of tissue into whole organs that are custom designed for the patient, limiting the possibility of rejection and alleviating the long wait times on transplant lists.
  • printedteeth1-143x214Antimicrobial teeth.  A boon to those of us with an arduous dental history, the development of bacteria-resistant tooth implants may be more than a distant fever dream. Dutch scientists have printed and initially tested tooth prototypes against human saliva, but are still a ways off from starting patient trials.
  • Smart textiles. When it comes to wearables, 3D printing is appearing in some surprising ways. Take this architectural swimsuit top meant to help clean the ocean  by locking aquatic contaminants away in its fabric. Or this Anouk Wipprecht design of a “spider” dress that responds to the wearer’s emotional state. A great deal of industry seems to be focused on the concept of wearable electronics, which is sure to gain momentum from the recent production of a flexible graphene fabric.
4D-dress-012
4D Dress, Photo Credit: Steve Marsel Studio
  • The advent of 4D printing. Harvard researchers have revealed new research of 4D printing techniques that allows for the creation of materials that can interact with their environments and can experience temporal changes (thus adding a fourth dimension to 3D applications). They have developed mathematical models that can suggest exactly how the material is to be printed in order to produce the desired changes in shape. One of the primary suggested uses for 4D printing is the fabrication of self-building objects. But as presented in the photo above, the world of 4D printing and haute couture is also colliding.
  • Printing custom drug formulations. Lee Cronin at Glasglow University, as told to the Guardian in 2012, envisions a day where we would be able to print our prescriptions at home. The New York Times recently released this article about the continuing challenges of drug shortages that can arise from impacts to manufacturer facilities, or when drug production is limited due to concerns about bankability. The ability to more easily synthesize medical compounds could revolutionize the pharmaceutical industry.