Evolution of Human Height in the World | OurWorldInData.org

Poor nutrition and illness in childhood limit human growth. As a consequence, the average height of a population is strongly correlated with living standards in a population. This makes the study of human height relevant for historians who want to understand the history of living conditions.

Because the effect of better material living standards is to make people taller, human height is used as an indirect measure of living standards. It is especially relevant for the study of living conditions in periods for which little or no other data is available — what historians refer to as the pre-statistical period.

It is important to stress that height is not used as a direct measure of well-being. The variation of height within a given population is largely determined by genetic factors.1

The history of human height allows us to track progress against undernourishment and disease and makes it possible to understand who started to benefit from modern advancements and when.

Source and more detailed information: https://ourworldindata.org/human-height

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Best Online Periodic Table | Ptable.com

Ptable.com is a dynamic, web-based periodic table of elements that offers a powerful and intuitive interface for students, educators, and professionals alike. Unlike traditional printed tables, Ptable updates in real-time and integrates data-rich content like element properties, isotopes, and historical data, all presented in a highly interactive and user-friendly format.

Notable features:
Instant data access – Hover over or click any element to see detailed information including properties, electron configurations, and oxidation states.
Multiple views – Switch between physical, atomic, orbital, and isotopic views to suit your learning or research needs.
Multilingual support – Available in dozens of languages, making it accessible to a global audience.
Real-time updates – Constantly maintained with up-to-date scientific information.
Mobile-friendly – Works smoothly across devices without needing to install anything.

Year of discovery comparison

Ptable.com – Focus on year of discovery (the elements in white were not discovered on 1999)

Boiling point comparison

Ptable.com – Focus on boiling point for each element on a linear scale (you can change the color or the type of scale)

Les Vers de terre pèsent plus lourd que tous les autres animaux réunis !


Les vers de terre constituent la moitié de la biomasse animale terrestre.

1. Le poids écrasant des vers de terre

Un monopole inattendu
Selon une étude publiée dans PNAS (2018, voir source en bas de ce post), les vers de terre représentent environ 1,2 milliard de tonnes métriques, soit 50% de la biomasse animale terrestre totale.

En comparaison (voir tableau plus bas) :
Le bétail domestique (vaches, porcs, moutons) pèse 600 millions de tonnes (25%).
Les humains atteignent 60 millions de tonnes (2,5%).
Tous les mammifères sauvages (éléphants, loups, cerfs) ne totalisent que 20 millions de tonnes (0,8%).

Cette domination s’explique par leur densité phénoménale : dans une prairie fertile, on peut trouver jusqu’à 1 million de vers par hectare, pesant collectivement 1 à 3 tonnes.

Pourquoi une telle abondance ?
Une adaptation parfaite : Présents sur tous les continents (sauf déserts et glaciers).
Un cycle de vie rapide : Certaines espèces produisent 100 œufs par an.
Peu de prédateurs directs : Les taupes et oiseaux en mangent, mais pas assez pour limiter leur expansion.

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Dragon Ball | Mangas et Films

Mangas

TitreVolumesDatesCanonScénarioPériode
Dragon Ball421984–1995ToriyamaEnfance de Goku → Fin de l’arc Boo
Dragon Ball Super242015–en coursToriyamaPost-arc Boo (avant l’épilogue de DBZ)
Jaco the Galactic Patrolman12013🔶ToriyamaPréquel (lié à l’origine de Goku)
Dragon Ball Minus12014ToriyamaOrigine de Goku (intégré à Broly)
Dragon Ball SD (Super Deformed)102010–en coursOoishiParodie des arcs classiques
Légende :

✅ Canon : Fait partie de l’histoire principale approuvée par Toriyama.
🔶 Semi-canon : Éléments partiellement intégrés (ex : Jaco explique des détails de Super).
❌ Non-canon : Œuvres dérivées sans impact sur la timeline officielle.

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Maps of Pre-Columbian Civilizations

Pre-Columbian civilizations refer to the societies and cultures that thrived in the Americas before the arrival of Christopher Columbus in 1492. These civilizations, including the Maya, Aztec, and Inca, developed advanced knowledge in architecture, astronomy, agriculture, and governance, leaving a lasting impact on history despite their decline following European colonization.

Source: Britannica

Petite Histoire de Responsabilité

 

C’est l’histoire de quatre individus : Chacun, Quelqu’un, Quiconque et Personne.

Un travail important devait être fait, et on avait demandé à Chacun de s’en occuper :

  • Chacun était assuré que Quelqu’un allait le faire.
  • Quelqu’un s’est emporté parce qu’il considérait que ce travail était la responsabilité de Chacun.
  • Chacun croyait que Quiconque pouvait le faire, mais Personne ne s’était rendu compte que Chacun ne le ferait pas.

À la fin, Chacun blâmait Quelqu’un, du fait que Personne n’avait fait ce que Quiconque aurait dû faire.

Brooks’ Law | Bigger Teams, Bigger Problems?

When a project falls behind schedule, the knee-jerk reaction is often to add more people to the team. But does this actually help? According to Brooks’ Law, the answer is a resounding no. In fact, it might make things worse.

📉 𝐁𝐫𝐨𝐨𝐤𝐬’ 𝐋𝐚𝐰 𝐢𝐧 𝐚 𝐍𝐮𝐭𝐬𝐡𝐞𝐥𝐥
“Adding manpower to a late project makes it later.”
More people = more complexity, not more progress.

💡 𝐖𝐡𝐲 𝐁𝐢𝐠𝐠𝐞𝐫 𝐓𝐞𝐚𝐦𝐬 𝐁𝐚𝐜𝐤𝐟𝐢𝐫𝐞
● 𝐑𝐚𝐦𝐩-𝐔𝐩 𝐓𝐢𝐦𝐞: New team members need time to get up to speed, pulling focus and resources away from the project.
● 𝐂𝐨𝐦𝐦𝐮𝐧𝐢𝐜𝐚𝐭𝐢𝐨𝐧 𝐎𝐯𝐞𝐫𝐥𝐨𝐚𝐝: More people mean more meetings, emails, and misaligned priorities. Coordination becomes a bottleneck.
● 𝐃𝐢𝐦𝐢𝐧𝐢𝐬𝐡𝐢𝐧𝐠 𝐑𝐞𝐭𝐮𝐫𝐧𝐬: Not all tasks can be easily divided, and adding more hands can lead to duplicated efforts or confusion.

🔑 𝐇𝐨𝐰 𝐭𝐨 𝐀𝐯𝐨𝐢𝐝 𝐭𝐡𝐞 𝐏𝐢𝐭𝐟𝐚𝐥𝐥𝐬
● 𝐒𝐭𝐢𝐜𝐤 𝐭𝐨 𝐒𝐦𝐚𝐥𝐥𝐞𝐫, 𝐒𝐤𝐢𝐥𝐥𝐞𝐝 𝐓𝐞𝐚𝐦𝐬: Focus on quality over quantity. A smaller, highly skilled team can often outperform a larger, less cohesive one.
● 𝐒𝐭𝐫𝐞𝐚𝐦𝐥𝐢𝐧𝐞 𝐂𝐨𝐦𝐦𝐮𝐧𝐢𝐜𝐚𝐭𝐢𝐨𝐧: Use tools and processes that minimize friction and keep everyone aligned.
● 𝐀𝐝𝐝𝐫𝐞𝐬𝐬 𝐑𝐨𝐨𝐭 𝐂𝐚𝐮𝐬𝐞𝐬: Instead of adding people, identify and fix the underlying issues causing delays.
● 𝐏𝐥𝐚𝐧 𝐟𝐨𝐫 𝐑𝐞𝐚𝐥𝐢𝐬𝐭𝐢𝐜 𝐓𝐢𝐦𝐞𝐥𝐢𝐧𝐞𝐬: Avoid overpromising and set achievable goals from the start.

🌟 𝐓𝐡𝐞 𝐁𝐢𝐠 𝐓𝐚𝐤𝐞𝐚𝐰𝐚𝐲: More people ≠ More productivity. The right team size matters!

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