12 amazing fossil finds of 2015
See link for photos and further links to articles on each fossil.

600 million years ago
Ancient sponge ancestor
Barely the size of a pinhead, this tiny creature (called Eocyathispongia qiania) had tubular chambers and surface cells that resemble those of modern sponges (SN: 4/4/15, p. 12).

460 million years ago
Earliest sea scorpion
The remains of this sea monster (Pentecopterus decorahensis) were found in an ancient impact crater in Iowa. It grew up to 1.7 meters long and had bristly, serrated limbs (SN: 11/14/15, p. 5).

300 million years ago
Texas supershark
The oldest known supershark was 8.5 meters long, larger than today’s great whites. It swam in warm seas over what’s now Texas (SN Online: 10/20/15).

231 million years ago
This croc ancestor, Carnufex carolinensis, which stretched 3 meters and may have walked on two legs, was a top predator in what’s now North Carolina, hence its fearsome nickname (SN: 4/18/15, p. 16).

167 million years ago
Jurassic snakes
Four newly identified species suggest that snakes appeared 70 million years earlier than thought, living alongside the dinosaurs (SN: 2/21/15, p. 11). The tip-off: skulls like modern snakes, with teeth that curve backward.

165 million years ago
Early tree climber
Chinese fossils suggest this shrew-sized creature had curved claws for climbing. Agilodocodon scansorius is the oldest known tree dweller among docodonts, ancient kin of today’s mammals (SN Online: 2/12/15).

150 million years ago
Vegetarian T. rex relative
This dino, Chilesaurus diegosuarezi, had a T. rex’s tiny forearms and sturdy legs. But not-so-sharp teeth suggest it ate plants, a sign that not all theropods were carnivores (SN: 5/30/15, p. 8).

130.7 million years ago
Oldest modern birds
Feather-flecked, hummingbird-sized fossils of this water wader, Archaeornithura meemannae, found in China, push the earliest record of modern bird relatives back 6 million years (SN: 6/27/15, p. 5).

120 million years ago
Four-legged snake
An elusive link between snakes and lizards turned up in a German museum specimen. The leggy fossil find hints that snakes might have evolved on land (SN: 8/22/15, p. 10).

69 million years ago
New Arctic dino
This newfound duck-billed dino, Ugrunaaluk kuukpikensis, joins about a dozen other dinosaurs that roamed the chilly, polar forests and endured long stretches of darkness (SN: 10/31/15, p. 5).

11.6 million years ago
Gibbonlike ape ancestor
The remains of a small tree dweller, dubbed Laia but officially Pliobates cataloniae, suggest that today’s apes descended from small primates instead of large ones, as scientists had believed (SN: 11/28/15, p. 10).

3.5 million years ago
Terror bird
This South American predator (Llallawavis scagliai), one of many prowling the continent, stood 1.2 meters tall and used its extra sturdy beak as a hatchet when hunting (SN: 5/2/15, p. 11).

Thanks, mollwollfumble.

231 million years ago This croc ancestor, Carnufex carolinensis, which stretched 3 meters and may have walked on two legs,

That would look weird as shit.

dv said:

Thanks, mollwollfumble.

231 million years ago This croc ancestor, Carnufex carolinensis, which stretched 3 meters and may have walked on two legs,

That would look weird as shit.

It’s an interesting one. I’ve known for a while that some ancient crocs were facultative bipeds. eg. Hesperosuchus

and Erpetosuchus

Here’s the new one

There’s no way that man could have walked the same earth as those.

roughbarked said:

There’s no way that man could have walked the same earth as those.

True. The follow-up question is obviously “What’s the slowest that the Earth’s surface can change?”

mollwollfumble said:

roughbarked said:

There’s no way that man could have walked the same earth as those.

True. The follow-up question is obviously “What’s the slowest that the Earth’s surface can change?”

In most cases around where I live that would be, imperceptible to the average human life span.

roughbarked said:

mollwollfumble said:

roughbarked said:

There’s no way that man could have walked the same earth as those.

True. The follow-up question is obviously “What’s the slowest that the Earth’s surface can change?”

In most cases around where I live that would be, imperceptible to the average human life span.

Not here. Garden pavers tend to pick up a few mm of soil on them in only a couple of years.
Australian lakes sediment up at rates ranging from 0.2 to 20 mm per year.
In the house I grew up in the side fence was migrating downhill with the topsoil again several mm per year.

There are dry, windswept parts of Antarctica that change verrrry slowly

dv said:

There are dry, windswept parts of Antarctica that change verrrry slowly

The whole of the Antarctic ice sheet is mighty young, compared to the geological timescale. 4,000 m of continuous rise in the last 400,000 years is an average of 1 cm rise per year, which is faster than most places on Earth.

mollwollfumble said:

roughbarked said:

mollwollfumble said:

True. The follow-up question is obviously “What’s the slowest that the Earth’s surface can change?”

In most cases around where I live that would be, imperceptible to the average human life span.

Not here. Garden pavers tend to pick up a few mm of soil on them in only a couple of years.
Australian lakes sediment up at rates ranging from 0.2 to 20 mm per year.
In the house I grew up in the side fence was migrating downhill with the topsoil again several mm per year.

Well, I did change things around here. For a start I removed the weeds, nothing but thistles. Brought in a couple of hundred tonnes of grape marc for mulch. Then I planted lots and lots of trees. Now the wind doesn’t blow any soil deposits away and the trees have added to the humus layer. So indeed trees have reached 30 metres tall and the groundflora is 90% native now.Things have changed perceptibly here in half my lifetime.

600 million years ago
Ancient sponge ancestor
Barely the size of a pinhead, this tiny creature (called Eocyathispongia qiania) had tubular chambers and surface cells that resemble those of modern sponges (SN: 4/4/15, p. 12).

460 million years ago
Earliest sea scorpion
The remains of this sea monster (Pentecopterus decorahensis) were found in an ancient impact crater in Iowa. It grew up to 1.7 meters long and had bristly, serrated limbs

The above two are of great interest to me. The sponge is so early that it’s in the ediacaran, and given that almost everything else at that time had a sheetlike form, that makes it a tentative ancestor of all multicellular animals (but I don’t believe that). It certainly makes it the earliest confirmed multicellular animal that has current descendants.

I’d like to see a direct comparison of the claws of the first sea scorpion and the so-called headless shrimp claws of anomalocaris. I want to test the hypothesis that the latter is the ancestor of the former.