An Evolving Planet

Appreciating our place in the 3.5 billion year history of life on Earth.

[oupacademic]

What better way to celebrate the birthday of Charles Darwin than by checking out some must-read books about the life and theories of this revered scientist?

On the Origin of Species, Revised Edition. By Charles Darwin; edited by Gillian Beer

Evolutionary Writings: Including the Autobiographies. By Charles Darwin, edited by James A. Secord

Darwin: A Very Short Introduction by Jonathan Howard

Evolution: A Very Short Introduction by Brian Charlesworth

Darwin and His Children: His Other Legacy by Tim M. Berra

Alfred Russel Wallace: Letters from the Malay Archipelago by John van Wyhe and Kees Rookmaaker

Darwin the Writer by George Levine

Darwin in the Archives: Papers on Erasmus Darwin and Charles Darwin from the Journal of the Society for the Bibliography of Natural History and Archives of Natural History by E. Charles Nelson and Duncan Porter

Darwin’s Camera: Art and Photography in the Theory of Evolution by Phillip Prodger

Living with Darwin: Evolution, Design, and the Future of Faith by Philip Kitcher

In Darwin’s Shadow: The Life and Science of Alfred Russel Wallace: A Biographical Study on the Psychology of History by Michael Shermer

Erasmus Darwin: Sex, Science, and Serendipity by Patricia Fara

Happy reading! But most importantly—happy birthday, Darwin!

[the-holocene-extinction]

Hawksbill Sea Turtle (Eretmochelys imbricata)-

Conservation status- Critically endangered

The hawksbill sea turtle is one of the most critically endangered species of sea turtle. Over the last three generations a decrease in the number of recorded nesting females has declined by between 84 and 87 percent. 

The primary threat to these turtles is from illegal trade. Despite being a protected species many individuals are killed for their shells and other products. Many turtles are also killed accidentally due to fishing bycatch. They can easily become tangled in fishing nets or get caught on fishing lines.

Learn more and get involved:

National Geographic

Sea Turtle Conservancy

World Wildlife Foundation

Encyclopedia of Life

[unknown-endangered]

Cayman Island blue iguana (Cyclura lewisi)

Endangered on the IUCN Red List.

Cyclura lewisi gets its famous blue colour during the breeding season. It is endemic to Grand Cayman, and now only lives in the High Rock Battle Hill area. It is solitary, and females defend their territories from males by giving head bobbing signals. It feeds on a wide range of foods from up to 45 different types of plant, and may also eat fruit and fungi. 

Numbers of C. lewisi have been falling for decades, and this decline is speeding up due to deforestation and land development. Other threats include hunting by farmers, road accidents, and predation by cats and dogs. 

C. lewisi is listed under Appendix I of CITES, which prohibits international trade. The National Trust for the Cayman Islands is running a programme that aims to breed and reintroduce this iguana into its range. It will also educate local people and protect C. lewisi's bushland habitat.

Photo: H. Michael Miley on Wikimedia Commons.

[rhamphotheca]

Years After Mating, Eagle Rays Finally Give Birth

by Stephen Messenger

The marine biologists at Australia’s Oceanworld Manly aquarium may be well-versed in the facts of life, but it’s never too late to learn a bit more about how exactly babies are made. Recently, twelve healthy baby rays were birthed at the facility by a pair of females, much to the confusion of aquarium staff. What’s so puzzling about that? Well, the new mothers haven’t had any contact with a male stingray for over two years.

Researchers point out that some female marine animals, like rays and sharks, have been known to store sperm until just the right moment to conceive. But, according to a report from Australia’s Daily Telegraph, never before have biologists observed rays put off starting a family so long after the initial reproductive deed was done. In fact, pregnancy was the last thing on their minds when they noticed two of their rays were starting to plump up…

(read more: TreeHugger)

Photo: chucklepix

[ewilloughby]

Here’s a slightly older illustration that I never put on Tumblr, and my blog is full of feathers and dinosaurs, so how about some pterosaurs and pycnofibers for a change instead?

This is a trio of Pteranodon longiceps, two males and a female. It’s a modification/cropping of a larger illustration, a dromaeosaurid digging scenario. 

[animaltoday]

Four Eyed Turtle (Sacalia quadriocellata)

Often confused with the Beal’s Eyed Turtle, which has 2 ocella without the black center.  These small turtles grow to about 5 inches long and are native to Southern China.  They live in small ponds and rivers and are adept at climbing rocks and banks.

The coloration of this turtle varies between individuals.  The neck stripes can go from pale yellow to pink to dark red.  The irises can be yellow, green or dark brown.  There is speculation that some males have interbred with other species to create hybrid species, but the designs are so similar that it is difficult to distinguish as its own species.  They feed on small invertebrates, aquatic plants and some fruits. 

Like many turtles, especially in Asia, it is endangered.  Over hunting and pet trade brings their population number down by a large percentage. Many of the turtles sold have health problems or mutations.  

Photos: (top) (bottom left) (bottom right) 

[rhamphotheca]

Pacific Giant Octopus (Enteroctopus dofleini)

The world’s largest octopus lives on the Pacific coasts of North America and Asia. Known as the Giant Pacific Octopus, or the North Pacific Giant Octopus, it can grow as large or larger than you in its 3-5 year lifespan - its arm-span might exceed 14 ft (4.3 m).

They typically live at depths of around 215 feet (65 m), and use their suckers to catch smaller invertebrates and fish, though they’ve been known to take larger prey such as the small shark Spiny Dogfish, Squalus acanthias.

The species is semelparous - that is, they reproduce only once and then die, much like Pacific salmon. Females lay up to 100,000 eggs, which are fertilized by the male’s spermataphore, a “package” of sperm that can be up to 3.3 ft (1 m) long. The females guard their eggs until they hatch; they stop hunting and eventually die of starvation.

Octopuses are commonly considered the most intelligent of invertebrates; captive individuals have demonstrated the ability to problem-solve, such as learning to twist the lid off a screw-top jar to get at food inside.

photo by canopic on Flickr

(via:Peterson Field Guides)

[rhamphotheca]

Deep Sea Squid With Sectacular Tentacular Tips That Swim on Their Own

MBARI media release

Many deep-sea animals such as anglerfish use parts of their body as lures to attract prey. Some deep-sea squids may use this strategy as well. In a recent paper, researchers associated with the Monterey Bay Aquarium Research Institute (MBARI) describe a deep-sea squid that appears to use a different method to lure prey—its tentacle tips flap and flutter as if swimming on their own. The researchers hypothesize that the motion of these tentacle tips may induce small shrimp and other animals to approach within reach of the squid’s arms.

Most squids have eight arms and two longer “feeding” tentacles. The tips of the tentacles, which are often broader and armed with suckers or hooks, are known as “clubs.” Such squids hunt by rapidly extending their tentacles and then grabbing prey with their clubs. The squids also use the tentacles to carry captured prey to their mouths.

The deep-sea squid Grimalditeuthis bonplandi seems to use a very different feeding strategy. A slow swimmer with a weak, gelatinous body, its tentacles are long, thin, fragile, and too weak to capture prey. Unlike any other known squid, its tentacles do not have any suckers, hooks, or photophores (glowing spots)…

(read more about this awesome fucking squid)

[ho11irx]

[rhamphotheca]

Florida Cottonmouth (Agkistrodon piscivorus conanti) males combat while on the scent trail of a female.

[rhamphotheca]

The New Granada cross-banded tree frog, Smilisca phaeota, inhabits lowland humid forests from Honduras to Ecuador. It is also common in habitats disturbed by humans, such as plantations, rural gardens, canals and ditches in urban areas. These frogs can change the color of their upper surface. They are usually tan during the day and may change to bright green during the night. More about this frog: Encyclopedia of Life Image by Brian Gratwicke via Flickr 

[rhamphotheca]

The Greater Rhea (Rhea americana) is the largest bird in South America, at almost 5 ft in height and weighting up to 60 lbs. This large flightless bird feeds mainly on plant matter, including leaves, roots, seeds and fruits. It also takes insects and small animals, such as lizards, frogs, small birds and even snakes, and sometimes catches flies that have gathered around carrion. The greater rhea also commonly swallows pebbles, which help to grind down food in the gizzard, and can often be seen feeding alongside herds of pampas deer, guanacos, vicunas, or domestic livestock…

Learn more: Encyclopedia of Life Image Credit: Cláudio Dias Timm, Flickr

[giraffeinatree]

Fire Salamander (Salamandra salamandra), Eastern Europe

(photo: Rostislaw Shivrinskiy)

[tomial-deactivated20170205]

When you ask about my favorite animal, Giant Anteaters (Myrmecophaga tridactyla) are on the list. 

[Photo by Smithsonian National Zoo.]

[rhamphotheca]

All this week is (Inter)National Moth Week:

Its a global citizen science initiative intended to help people discover the fascinating world of moths. If you take part this week, and live in the eastern US, you might encounter this guy…

The Regal Moth (Citheronia regalis), family Saturniidae (silk moths). With a wingspan of up to 6 inches (15 cm), it’s among our largest moth species. Adults have no mouthparts and cannot feed; they may live only a week after emerging from their cocoon. The caterpillars are often known by the name Hickory Horned Devil for their striking appearance. Like the adults, the larvae are also huge - about 5.5 inches (14 cm) long; they are bright green with long orange horns, and while they do have mouthparts, they’re also harmless. For more information about National Moth Week, including how to join in or find participating locations near you, visit http://nationalmothweek.org/ Photo by Vilseskogen on Flickr

(via: Peterson Field Guides)

[astronomy-to-zoology]

Eastern Barred Bandicoot (Perameles gunnii)

…a small species of bandicoot that are native to Tasmania and southern Australia. Like other bandicoots the eastern barred bandicoot is nocturnal and will emerge at night to feed on insects on earthworms. During the day it will rest in a self made burrow. It uses its long nose as  a probe to locate and consume its prey.

Although it is listed as near threatened the eastern barred bandicoot is still suffering from habit loss and introduced predators. Its range was once distributed across Tasmania but now it is restricted to the eastern side of the island.

Phylogeny

Animalia-Chordata-Mammalia-Marsupialia-Peramelemorphia-Peramelidae-Perameles-P.gunnii

Images: JJ Harrison and australianfauna.com

[rhamphotheca]

Eggs of the Seepage Salamander (Desmognathus aeneus), family Plethodontidae ("Lungless Salamanders"), Nantahala National Forest, North Carolina, USA

(photos: Dave Huth)

[rhamphotheca]

What Good Is Half a Sucker?

by Carl Zimmer

The remora is so ridiculous that no one would try to make it up. The top of its head is a giant, flat suction cup. It uses the cup to lock onto the bodies of bigger animals, such as sharks, sea turtles, and whales. As the big animal swims for miles in search of a meal, the remora hangs on for the ride. When its host finds a victim, the remora detaches and feasts on the remains. It sometimes cleans its host’s body and mouth of parasites, and then clamps its head back on for another ride.

The remora’s ridiculousness makes it a fascinating evolutionary puzzle just waiting for the solving. Other species clamp themselves onto other animals–whale barnacles, for example, grow prongs from their shells that anchor them to whale skin–but among fish, remoras are exceptional. Their closest relatives include Mahi-Mahi and amberjacks, neither of which has anything on their head that even faintly resembles the remora’s sucker. Only after the ancestors of remoras and these ordinary fish split apart some 50 million years ago, the remoras evolved a remarkably new piece of anatomy.

When you look closely at the remora’s suction disk, its remarkableness only grows. It looks like a spiked Venetian blind. Pairs of slat-like bones called lamellae form a series of rows running down the length of its head, and muscles running from the remora’s skull to those bones pivot them, creating spaces between the rows…

(read more: National Geo - The Loom)

Photos by Mauritio Handler/National Geographic, Heather Perry/National Geographic, and Matt Friedman.