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Pass the Grouper but spare the fish sauce! Lunch time in Roman Tunisia!

Residents of Leptiminus, a city in Roman occupied Tunisia, ate a diet heavy in vegetables and marine life (including Grouper). However they avoided millet and legumes, dietary staples in other parts of the Empire.

They also avoided eating large amounts of the local fish sauce which they were trying to sell to other people. These are the findings of a Canadian science team that analyzed skeletons from the cemetery of Leptiminus.

The scientists were led by Professor Anne Keenleyside of Trent University in Peterborough.

The skeletons they analyzed date from the 2nd century A.D. to 5th century A.D. To determine the societys diet, the team used a method called stable carbon isotope analysis. Simply put this form of analysis measures the amount of different isotopes of carbon in the bone. Depending on the diet a person eats during their life, these amountswill be different.

So, how much did they like their fish at Leptiminus? A lot!

In fact the analysis says that people in the settlement ate a significantly higher proportion of marine animals than those in Portus, a harbour just south of Rome. They alsohad a bigger portion thanthe residents ofPoundbury camp inDorchester England. A fact that is not terribly surprising considering that raisingand hunting animals in Italy or England was likely a bit easier than in North Africa.

But what kind of fish were they eating?

Lentil, pea, and grass pea were well represented.

It definitely wasnt the food they were trying to sell to other people.

Fish Sauce (Garum) was exported from North Africa, including Leptiminus. However, the local fish sauce has an isotope value that is different than those found in the skeletons, so that isnt the culprit.

The scientists think that people were eating a variety of high trophic fish including sea bream and grouper. They may also have also been eating octopus, squid, anglerfish, mackerel and mullet.

Fish bones representing primarily gilthead sea bream and grouper have been recovered from Leptiminus, the scientists say in their research report.

Two things the residents didnt consume were millet and legumes. The scientists found no evidence in their analysis that the residents consumed a significant amount of those.

Instead, the residents appear to havestuck to their vegetables. The scientists finish offthe discussionchapter, in their research report,by noting that archaeologists have found that in the Roman-era farms of the Libyan pre-desert, lentil, pea, and grass pea were well represented.

Prehistoric fish pioneers sex

Sex involving ‘penetration’ is part of life for at least 380 000 000 years.That’s way longer than what we suspected. Internal fertilization was common with prehistoric fishes that lived at old tropical coral reefs during the Devonian, writes Nature, in a article that casts a new light on the history of sex with vertebrate animals, and thus also us humans.

The new discovery is that these ancient placoderms had developed this advanced form of mating well before the sharks. The prove that the fished did have internal fertilisation, was provided by the male fish fosiles.Those had an extra piece of bone at the height of the pelvis.

The new discovery of embryos in placoderm fishes belonging to the arthrodire group was a complete surprise to me,” Dr Long said. We werent expecting them, as these fish had showed no visible signs of sexual dimorphism where males and females have differing external body forms. Then we started looking closely at the rear paired fins on the fish Incisoscutum and found new structures not previously seen by other scientists. These features turned out to be same the structures they used for copulation.

The pelvic fins in fishes eventually evolved into the legs of modern land animals. They share a similar bone pattern in advanced fossil fishes to that of all animals (femur, tibia, fibula). In ancient placoderms the structure is much more primitive. The new find shows that the pelvic fins in these placoderms bore a long extra lobe, probably used for transferring sperm from the males to the females.

Further clues came from re-examination of other placoderm fishes from the Mount Howitt site in central Victoria. One fish, Austrophyllolepis, showed peculiar, long structures attached to the pelvic fin, which the research team couldnt explain previously. The evidence for the embryos then made sense.

These fish had pelvic fins built on the same pattern as those in modern sharks. All modern sharks have internal fertilisation, with males inserting parts of the pelvic fin called claspers inside the females for reproducing.

The Museum Victoria has a video illustration this process, bet you’ll click it? 😉