Earlier this year, scientists announced the mother of all placental mammals. Their discovery wasn’t due to an unburied fossil, but rather a database called MorphoBank.

The researchers used both genetic and physical traits of known animals (living and extinct) to reconstruct this common ancestor that likely diversified after the extinction of dinosaurs 65 million years ago.

The scientists recorded observational traits for 86 placental mammal species, including 40 fossil species. The resulting database contains more than 12,000 images that correspond to more than 4,500 traits detailing characteristics like the presence or absence of wings, teeth and certain bones, type of hair cover and brain structures. The dataset is about 10 times larger than information used in previous studies of mammal relationships. On MorphoBank, this study is known as Project 773. And it’s just one of nearly a thousand such projects…

MorphoBank began over ten years ago as a partnership between several institutions to create a “web application providing an online database and workspace for evolutionary research, specifically systematics (the science of determining the evolutionary relationships among species),” according to its website.  The information is open to everyone and the framework provides access to computing power that scientists might not otherwise have.

Cassie Graff, the Early Childhood Program Lead here at the Academy, was an undergraduate at UC San Diego in 2009, when the San Diego Supercomputing Center (SDSC) was looking to beta test MorphoBank. The SDSC wanted to determine how actual researchers would use the application and reached out to their local colleagues.

Annalisa Berta, an evolutionary biologist at San Diego State University, was working on a long-term project to create a morphology matrix of whales at the time, and it seemed a perfect fit for MorphoBank. Berta and her team, which included Graff, entered several morphological characteristics of extinct and extant (living) whales into the database. Graff entered color patterns like streaks and saddles and flipper coloration as codes into the matrix. This work eventually became Project 182 on MorphoBank.

“The database includes not only morphological traits, but also can provide genetic data and images to create taxonomic trees,” Graff explains. “It can hold all of your research and later everyone can access it, anyone can download matrices.”

For a more recent project, MorphoBank approached Academy and UC Davis postdoc Hannah Wood. They asked about her recent publication on pelican spiders and wanted to make the morphological datasets within that article available. Generally these datasets appear as an appendix to a publication. “MorphoBank makes it much easier for other scientists to access the data,” says Wood. And it’s important that scientists have that access, she explains. Her co-author, the Academy’s Charles Griswold, agrees. “One could look at other, existing spiders to see similarities and identify a new find.” Their pelican spiders are Project 847 on MorphoBank.

As researchers work to revise and grow the tree of life, they need to build upon the work of scientists that came before—and leverage the work of their modern day colleagues. MorphoBank, along with similar applications, promises 21st-century solutions to studies that began centuries ago.

With the rate our world is changing and warming, there’s an urgency to cataloging and monitoring Earth’s diversity. Traditional efforts are often expensive and require many scientist- (and citizen scientist-) hours visiting remote lands that are often inaccessible.

But researchers are discovering other ways to monitor regional biodiversity and animal populations. Last year, Danish scientists found they could extract mammal DNA from leeches’ last blood meals. Now, German researchers are grabbing mammal DNA from widespread carrion flies.

Carrion flies (Calliphoridae and Sarcophagidae) feed on animal corpses, open wounds, and feces. While disgusting, the flies are widely distributed, found in diverse habitats and, perhaps most importantly, easy to catch. And since they don’t have acids in their guts like we do, scientists are able to retrieve viable DNA fragments from their stomachs.

For a recent study, published in the February 2013 issue of Molecular Ecology, the German scientists looked at carrion fly guts from two different forests—Taï National Park in Côte d’Ivoire, a rainforest, and the Kirindy Forest in Madagascar, a dry, deciduous forest. Among the mammals identified from the DNA fragments in the carrion flies were monkeys, lemurs, rodents, shrews, antelope, bats and even a hippopotamus. The DNA also revealed two bird species and one amphibian species.

Using deep sequencing technology, researchers are able to identify exact species, and hopefully at some point, they can glean information about population sizes and the spread of diseases.

The authors of the recent paper argue that with carrion flies and leeches performing their normal, albeit gross duties, perhaps scientists and conservationists can have entire armies of biodiversity monitors in the field.

Calliphora vomitoria image: JJ Harrison/Wikipedia

The findings may help explain why mammals evolved such large and complex brains, which in some cases ballooned 10 times larger than relative body size. The authors reconstructed fossils of two Early Jurassic Period small shrew-like pre-mammals – Morganuocodon and Hadrocodium—using a medical imaging technique called X-ray computed tomography or CT.

The 3D images gave the researchers a magnified, inside view of the brain and nasal cavities of the fossils. The team observed that the nasal cavity and related smell regions were enlarged in the pre-mammal fossils, along with areas of the brain that process olfactory information. Both characteristics indicate an improved sense of smell in pre-mammals.

“Now we have a much better idea of the historical sequence of events and of the relative importance of the different sensory systems in the early evolution of mammals. It paints a much more vivid picture of what the ancestral mammal was like and how it behaved, and of our own ancestry,” says lead author Tim Rowe, of the University of Texas.

In fact, comparing the mammal brain endocasts with fossils of other groups, like those of primitive reptiles called cynodonts, revealed that the brains of the Morganuocodon and the Hadrocodium were almost 50 percent larger than the brains of mammal precursors.

Nature News reports that

With this foundation in place, later mammals could have siphoned off some of those resources for colour vision, echolocation and even, in the case of the platypus, the ability to sense electric currents.

Rowe says this is just step one. “Now that we have a general picture of the brain in mammals ancestrally, we plan to explore the subsequent diversification of the brain and sensory systems as mammals evolved and diversified. This will unlock new secrets about how huge brains and extreme sensory adaptations evolved in mammals… It is all very exciting!”

Image: Matt Colbert, Univ. of Texas at Austin

Her latest study is three years in the making and a collaboration with a team of pale­on­tol­o­gists, evo­lu­tion­ary biol­o­gists and macro­e­col­o­gists from uni­ver­si­ties around the world.  The team studied the growth of mammal size after the dinosaurs went extinct around 65 million years ago and published their results last week in the journal Science.

Smith and her colleagues found that mam­mals grew from a max­i­mum of about 10 kilo­grams (22 pounds) when they shared the Earth with dinosaurs to a max­i­mum of 17 tons after­wards. They found that this pat­tern was sur­pris­ingly con­sis­tent glob­ally and across time and trophic groups and lin­eages—that is, ani­mals with dif­fer­ing diets and/or descended from dif­fer­ent ances­tors.

From the Observations blog in Scientific American:

But across all of the major continents, during the first 25 million years after the dinosaurs were wiped out, mammals underwent an explosive growth spurt. By 42 million years ago, however, the researchers found, the intense growth had leveled off.

What was the peak of land mammal growth? Indri­cotherium tran­souralicum was the largest mam­mal that ever walked the Earth. It was a horn­less rhinoceros-like her­bi­vore that weighed approx­i­mately 17 tons, stood about 18 feet high at the shoul­der and lived almost 34 mil­lion years ago.

The overall results give clues as to what sets the lim­its on max­i­mum body size on land — the amount of space avail­able to each ani­mal and the cli­mate they live in. The colder the cli­mate, the big­ger the mam­mals seem to get, as big­ger ani­mals con­serve heat bet­ter.  The results also show that no one group of mam­mals dom­i­nates the largest size class.

Size does matter, says Smith, “Under­stand­ing the con­straints oper­at­ing on size is cru­cial to under­stand­ing how ecosys­tems work.”

Image: Alison Boyer/Yale University

Often we try and gather clues from extinction events to get hints about our future, but perhaps we’ve been missing the forest for the trees. Now, a team of researchers from Stanford and UC Berkeley are looking at past biodiversity loss for clues.

“If we only focus on extinction, we are not getting the whole story,” said Jessica Blois, PhD, lead author of a study published online in Nature yesterday.

Focusing on the last major warming event about 12,000 years ago, Blois and her Stanford colleague Elizabeth Hadly searched the Samwell Cave near Mt. Shasta for small mammal fossils. They also sampled the modern small mammal community by doing some live trapping in the area of the cave. (Jenny McGuire, a graduate student at the UC Berkeley, did the radiocarbon dating of the samples.)

They found big changes in the small mammal population. “In the Pleistocene, there were about as many gophers as there were voles as there were deer mice,” Hadly said. “But as you move into the warming event, there is a really rapid reduction in how evenly these animals are distributed.” As some species such as deer mice flourished, many other species declined.

Deer mice are considered a “weedy” species and, like the plants, don’t have a strong habitat preference—they are generalists that will move in wherever there is an opening. When they replace other small-mammal species, the effects ripple through the ecosystem.

“Small mammals are so common, we often take them for granted,” Blois said. “But they play important roles within ecosystems, in soil aeration and seed dispersal, for example, and as prey for larger animals.” And different small mammals play those roles differently. What’s more, “Even though all of the species survived, small mammal communities as a whole lost a substantial amount of diversity, which may make them less resilient to future change,” Blois said.

And according to Hadly, an extraordinarily rapid change is looming.

“The temperature change over the next hundred years is expected to be greater than the temperature that most of the mammals that are on the landscape have yet witnessed as a species,” she said.

Creative Commons image by r.i.c.h.