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System default

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Tutoring abilities

Did you know that a tiny Chihuahua and a giant Great Dane both share the exact same ancestor: the wild wolf?

Wolves didn't turn into friendly pets on their own — humans changed them on purpose over thousands of years.

A **trait** is any feature of a living thing, such as fur color, height, or running speed.

**Selective breeding** (also called **artificial selection**) happens when humans choose which parent plants or animals reproduce so their babies have the traits humans want.

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="1:1">
  <script src="{{VENDOR_CDN}}/classace-diagram.js"></script>
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      background: #f8f9fa;
      font-family: system-ui, -apple-system, sans-serif;
      color: #1e2945;
      padding: 16px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      user-select: none;
    }

    .grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      grid-template-rows: 1fr 1fr;
      gap: 12px;
      width: 100%;
      max-width: 440px;
      position: relative;
      margin: auto 0;
    }

    .step-card {
      background: #ffffff;
      border: 2px solid #e6e6e6;
      border-radius: 16px;
      padding: 12px 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      text-align: center;
      cursor: pointer;
      transition: box-shadow 0.25s ease, border-color 0.25s ease, transform 0.25s ease;
      min-height: 120px;
      position: relative;
    }

    .step-card.active {
      border-color: #22b7ff;
      box-shadow: 0 0 0 3px rgba(34, 183, 255, 0.2), 0 4px 12px rgba(30, 41, 69, 0.08);
      transform: translateY(-2px);
    }

    .step-badge {
      position: absolute;
      top: 8px;
      left: 8px;
      width: 22px;
      height: 22px;
      border-radius: 50%;
      background: #f1f5f9;
      color: #64748b;
      font-size: 11px;
      font-weight: 700;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: background 0.25s ease, color 0.25s ease;
    }

    .step-card.active .step-badge {
      background: #22b7ff;
      color: #ffffff;
    }

    .visual-box {
      height: 48px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 26px;
      margin-bottom: 4px;
      gap: 4px;
    }

    .step-label {
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
      line-height: 1.2;
    }

    /* Trait magnifying lens effect */
    .mag-lens {
      font-size: 20px;
      margin-left: -8px;
      margin-top: -12px;
    }

    /* Selected parents with checkmark badges */
    .parent-wrap {
      position: relative;
      display: inline-flex;
    }
    .check-tag {
      position: absolute;
      bottom: -2px;
      right: -4px;
      background: #10b981;
      color: white;
      font-size: 9px;
      font-weight: 900;
      width: 14px;
      height: 14px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      border: 1.5px solid #fff;
    }

    /* Generational comparison */
    .size-sm { font-size: 18px; opacity: 0.6; }
    .arrow-mini { font-size: 14px; color: #94a3b8; font-weight: bold; }
    .size-lg { font-size: 30px; }

    /* Center Cycle Symbol */
    .center-hub {
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      width: 38px;
      height: 38px;
      background: #ffffff;
      border: 2px solid #e6e6e6;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 18px;
      color: #64748b;
      box-shadow: 0 2px 6px rgba(0,0,0,0.06);
      pointer-events: none;
    }

    /* Controls bar */
    .controls {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 12px;
      margin-top: 10px;
    }

    .btn-play {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      border-radius: 20px;
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 600;
      color: #1e2945;
      cursor: pointer;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .btn-play:active {
      background: #f1f5f9;
    }

    .dots {
      display: flex;
      gap: 6px;
      align-items: center;
    }

    .dot {
      width: 9px;
      height: 9px;
      border-radius: 50%;
      background: #cbd5e1;
      cursor: pointer;
      transition: background 0.25s ease, transform 0.25s ease;
    }

    .dot.active {
      background: #22b7ff;
      transform: scale(1.2);
    }
  </style>
</head>
<body>

  <div class="grid">
    
    <div class="step-card active" id="step0" data-index="0">
      <div class="step-badge">1</div>
      <div class="visual-box">
        <span>🍓</span><span class="mag-lens">🔍</span>
      </div>
      <div class="step-label">Find Trait</div>
    </div>

    
    <div class="step-card" id="step1" data-index="1">
      <div class="step-badge">2</div>
      <div class="visual-box">
        <div class="parent-wrap">🍓<span class="check-tag">✓</span></div>
        <div class="parent-wrap">🍓<span class="check-tag">✓</span></div>
      </div>
      <div class="step-label">Pick Parents</div>
    </div>

    
    <div class="step-card" id="step3" data-index="3">
      <div class="step-badge">4</div>
      <div class="visual-box">
        <span class="size-sm">🍓</span>
        <span class="arrow-mini">→</span>
        <span class="size-lg">🍓</span>
      </div>
      <div class="step-label">Repeat</div>
    </div>

    
    <div class="step-card" id="step2" data-index="2">
      <div class="step-badge">3</div>
      <div class="visual-box">
        <span>🍓</span>
        <span class="arrow-mini">→</span>
        <span>🌱</span>
      </div>
      <div class="step-label">Breed Together</div>
    </div>

    
    <div class="center-hub">🔄</div>
  </div>

  <div class="controls">
    <button class="btn-play" id="playBtn">
      <span id="playIcon">⏸</span> Pause
    </button>
    <div class="dots">
      <div class="dot active" data-index="0"></div>
      <div class="dot" data-index="1"></div>
      <div class="dot" data-index="2"></div>
      <div class="dot" data-index="3"></div>
    </div>
  </div>

  <script>
    const cards = [
      document.getElementById('step0'),
      document.getElementById('step1'),
      document.getElementById('step2'),
      document.getElementById('step3')
    ];
    const dots = document.querySelectorAll('.dot');
    const playBtn = document.getElementById('playBtn');
    const playIcon = document.getElementById('playIcon');

    let current = 0;
    let playing = true;
    let timer = null;

    function setStep(index) {
      current = index;
      cards.forEach((c, i) => c.classList.toggle('active', i === current));
      dots.forEach((d, i) => d.classList.toggle('active', i === current));
    }

    function nextStep() {
      setStep((current + 1) % 4);
    }

    function startAuto() {
      stopAuto();
      timer = setInterval(nextStep, 3000);
      playing = true;
      playIcon.textContent = '⏸';
      playBtn.lastChild.textContent = ' Pause';
    }

    function stopAuto() {
      if (timer) clearInterval(timer);
      playing = false;
      playIcon.textContent = '▶';
      playBtn.lastChild.textContent = ' Play';
    }

    playBtn.addEventListener('click', () => {
      if (playing) stopAuto();
      else { nextStep(); startAuto(); }
    });

    cards.forEach(card => {
      card.addEventListener('click', () => {
        const idx = parseInt(card.dataset.index, 10);
        setStep(idx);
        if (playing) startAuto();
      });
    });

    dots.forEach(dot => {
      dot.addEventListener('click', () => {
        const idx = parseInt(dot.dataset.index, 10);
        setStep(idx);
        if (playing) startAuto();
      });
    });

    startAuto();
  </script>
</body>
</html>

How did farmers use this same trick to turn wild weeds into the food on your dinner plate?

Around 9,000 years ago, corn was a wild grass called *teosinte* with rock-hard kernels that were smaller than a dime.

Farmers saved seeds only from the plants with slightly softer, sweeter, and larger kernels to plant for the next year.

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    }

    body {
      width: 100%;
      min-height: 100%;
      background: #ffffff;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 12px;
    }

    .diagram-grid {
      width: 100%;
      max-width: 620px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 8px;
    }

    .crop-card {
      flex: 1;
      background: #ffffff;
      border: 1px solid #e6e6e6;
      border-radius: 12px;
      padding: 14px 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      min-width: 0;
    }

    .crop-title {
      font-size: 15px;
      font-weight: 700;
      color: #1e2945;
      margin-bottom: 4px;
      white-space: nowrap;
    }

    .crop-sub {
      font-size: 12px;
      font-weight: 600;
      color: #64748b;
      margin-bottom: 10px;
    }

    .svg-stage {
      width: 100%;
      height: 180px;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .svg-stage svg {
      max-height: 100%;
      max-width: 100%;
    }

    .stats-pill {
      margin-top: 10px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 20px;
      padding: 4px 10px;
      font-size: 12px;
      font-weight: 600;
      color: #334155;
      line-height: 1.3;
    }

    .transition-zone {
      flex: 0 0 110px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      padding: 0 4px;
    }

    .arrow-svg {
      width: 100%;
      height: 28px;
      margin: 6px 0;
    }

    .trans-label {
      font-size: 12px;
      font-weight: 700;
      color: #0284c7;
      line-height: 1.25;
    }

    @media (max-width: 480px) {
      .crop-title { font-size: 13px; }
      .crop-sub { font-size: 11px; }
      .stats-pill { font-size: 11px; padding: 4px 6px; }
      .transition-zone { flex: 0 0 85px; }
      .trans-label { font-size: 11px; }
      .svg-stage { height: 150px; }
    }
  </style>
</head>
<body>

  <div class="diagram-grid">
    
    <div class="crop-card">
      <div class="crop-title">Ancient Teosinte</div>
      <div class="crop-sub">Wild Ancestor</div>
      
      <div class="svg-stage">
        
        <svg viewBox="0 0 70 180" width="70" height="180">
          
          <path d="M 35 170 Q 34 90 36 20" stroke="#4ade80" stroke-width="3" stroke-linecap="round" fill="none" />
          <path d="M 35 150 Q 22 135 14 140" stroke="#22c55e" stroke-width="2" stroke-linecap="round" fill="none" />
          <path d="M 36 110 Q 48 95 56 100" stroke="#22c55e" stroke-width="2" stroke-linecap="round" fill="none" />
          
          
          <g fill="#78350f" stroke="#451a03" stroke-width="1.2">
            <polygon points="35,130 42,122 38,114 31,122" />
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            <polygon points="35,46 40,40 37,34 32,40" />
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          <g fill="#b45309" opacity="0.6">
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          </g>
          
          
          <path d="M 35 34 L 36 15" stroke="#15803d" stroke-width="1.5" stroke-linecap="round" />
        </svg>
      </div>

      <div class="stats-pill">
        ~2 in • 5–10 Hard Kernels
      </div>
    </div>

    
    <div class="transition-zone">
      <div class="trans-label">Thousands of Years</div>
      <svg class="arrow-svg" viewBox="0 0 100 28">
        <defs>
          <linearGradient id="arrowGrad" x1="0%" y1="0%" x2="100%" y2="0%">
            <stop offset="0%" stop-color="#38bdf8" />
            <stop offset="100%" stop-color="#0284c7" />
          </linearGradient>
        </defs>
        <path d="M 5 14 L 80 14" stroke="url(#arrowGrad)" stroke-width="4" stroke-linecap="round" stroke-dasharray="2 0" />
        <polygon points="76,6 94,14 76,22" fill="#0284c7" />
      </svg>
      <div class="trans-label">Selective<br>Breeding</div>
    </div>

    
    <div class="crop-card">
      <div class="crop-title">Modern Corn</div>
      <div class="crop-sub">Domesticated Crop</div>
      
      <div class="svg-stage">
        
        <svg viewBox="0 0 110 180" width="110" height="180">
          
          <rect x="50" y="152" width="10" height="22" rx="3" fill="#16a34a" />
          
          
          <path d="M 50 156 C 25 150 12 110 10 70 C 18 100 35 140 50 154" fill="#22c55e" stroke="#15803d" stroke-width="1" />
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          <path d="M 46 158 C 30 165 18 150 12 135 C 24 148 38 154 48 156" fill="#15803d" opacity="0.7" />
          <path d="M 64 158 C 80 165 92 150 98 135 C 86 148 72 154 62 156" fill="#15803d" opacity="0.7" />

          
          <ellipse cx="55" cy="85" rx="24" ry="65" fill="#eab308" />
          
          
          
          <g fill="#fde047" stroke="#ca8a04" stroke-width="0.8">
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          <path d="M 52 23 Q 48 10 40 4" stroke="#d97706" stroke-width="1" fill="none" opacity="0.8" />
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          <path d="M 57 23 Q 64 12 68 5" stroke="#d97706" stroke-width="1" fill="none" opacity="0.8" />
        </svg>
      </div>

      <div class="stats-pill">
        ~8 in • 500+ Soft Kernels
      </div>
    </div>
  </div>

</body>
</html>

What happens when people apply this same power of choice to animals?

When people wanted dogs to protect sheep, they bred the calmest, most protective dogs together.

When people wanted dogs to pull heavy sleds through the snow, they bred dogs with the thickest fur and strongest muscles.

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    }

    body {
      background-color: #f8f9fa;
      color: #1e2945;
      width: 100%;
      min-height: 100%;
      padding: 16px 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
    }

    .tree-container {
      width: 100%;
      max-width: 620px;
      display: flex;
      flex-direction: column;
      align-items: center;
      position: relative;
    }

    /* Ancestor Box */
    .ancestor-card {
      background: #ffffff;
      border: 2px solid #cbd5e1;
      border-radius: 14px;
      padding: 10px 18px;
      text-align: center;
      box-shadow: 0 3px 10px rgba(0, 0, 0, 0.05);
      z-index: 2;
      cursor: pointer;
      transition: border-color 0.25s, box-shadow 0.25s;
    }

    .ancestor-card:hover {
      border-color: #94a3b8;
      box-shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
    }

    .icon-large {
      font-size: 32px;
      line-height: 1.1;
      display: block;
      margin-bottom: 2px;
    }

    .title {
      font-weight: 700;
      font-size: 15px;
      color: #1e2945;
    }

    .badge-ancestor {
      display: inline-block;
      margin-top: 4px;
      padding: 2px 8px;
      background: #f1f5f9;
      color: #475569;
      font-size: 11px;
      font-weight: 600;
      border-radius: 20px;
      letter-spacing: 0.3px;
    }

    /* SVG Connecting Branches */
    .branch-svg {
      width: 100%;
      height: 52px;
      display: block;
      overflow: visible;
    }

    .branch-line {
      stroke: #cbd5e1;
      stroke-width: 2.5;
      stroke-linecap: round;
      fill: none;
      transition: stroke 0.3s, stroke-width 0.3s;
    }

    .branch-line.active {
      stroke-width: 3.5;
    }

    .branch-line.husky.active { stroke: #0284c7; }
    .branch-line.collie.active { stroke: #059669; }
    .branch-line.lap.active { stroke: #7c3aed; }

    .arrow-marker {
      fill: #cbd5e1;
      transition: fill 0.3s;
    }
    .arrow-marker.husky.active { fill: #0284c7; }
    .arrow-marker.collie.active { fill: #059669; }
    .arrow-marker.lap.active { fill: #7c3aed; }

    /* Breeds Grid */
    .breeds-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 10px;
      width: 100%;
      z-index: 2;
    }

    .breed-card {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 12px;
      padding: 10px 8px;
      text-align: center;
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
      cursor: pointer;
      transition: border-color 0.25s, box-shadow 0.25s;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 140px;
    }

    .breed-card:hover {
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    }

    .breed-card.husky.active {
      border-color: #0284c7;
      box-shadow: 0 0 0 2px rgba(2, 132, 199, 0.2), 0 4px 12px rgba(0, 0, 0, 0.06);
    }
    .breed-card.collie.active {
      border-color: #059669;
      box-shadow: 0 0 0 2px rgba(5, 150, 105, 0.2), 0 4px 12px rgba(0, 0, 0, 0.06);
    }
    .breed-card.lap.active {
      border-color: #7c3aed;
      box-shadow: 0 0 0 2px rgba(124, 58, 237, 0.2), 0 4px 12px rgba(0, 0, 0, 0.06);
    }

    .breed-icon {
      font-size: 26px;
      margin-bottom: 2px;
    }

    .breed-name {
      font-size: 13px;
      font-weight: 700;
      color: #1e2945;
      line-height: 1.2;
      margin-bottom: 2px;
    }

    .breed-sub {
      font-size: 11px;
      color: #64748b;
      margin-bottom: 6px;
    }

    /* Badges */
    .badge {
      font-size: 10px;
      font-weight: 600;
      padding: 3px 6px;
      border-radius: 6px;
      line-height: 1.2;
      width: 100%;
      margin-top: auto;
    }

    .badge-husky {
      background: #e0f2fe;
      color: #0369a1;
    }

    .badge-collie {
      background: #dcfce7;
      color: #15803d;
    }

    .badge-lap {
      background: #f3e8ff;
      color: #6b21a8;
    }

    /* Instructional Prompt */
    .instruction {
      margin-top: 12px;
      font-size: 12px;
      color: #64748b;
      display: flex;
      align-items: center;
      gap: 5px;
    }

    @media (max-width: 440px) {
      .breed-card {
        padding: 8px 4px;
        min-height: 132px;
      }
      .breed-name {
        font-size: 12px;
      }
      .breed-sub {
        font-size: 10px;
      }
      .badge {
        font-size: 9.5px;
        padding: 2px 4px;
      }
    }
  </style>
</head>
<body>

  <div class="tree-container">
    
    
    <div class="ancestor-card" id="ancestor">
      <span class="icon-large">🐺</span>
      <div class="title">Wild Wolf</div>
      <span class="badge-ancestor">Common Ancestor</span>
    </div>

    
    <svg class="branch-svg" viewBox="0 0 300 50" preserveAspectRatio="none">
      <defs>
        <marker id="arrow-husky" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="4" markerHeight="4" orient="auto-start-reverse">
          <path d="M 0 1.5 L 8 5 L 0 8.5 z" class="arrow-marker husky active" />
        </marker>
        <marker id="arrow-collie" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="4" markerHeight="4" orient="auto-start-reverse">
          <path d="M 0 1.5 L 8 5 L 0 8.5 z" class="arrow-marker collie active" />
        </marker>
        <marker id="arrow-lap" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="4" markerHeight="4" orient="auto-start-reverse">
          <path d="M 0 1.5 L 8 5 L 0 8.5 z" class="arrow-marker lap active" />
        </marker>
      </defs>
      
      <path id="path-husky" d="M 150 0 C 150 24, 50 16, 50 42" class="branch-line husky active" marker-end="url(#arrow-husky)" />
      
      <path id="path-collie" d="M 150 0 L 150 42" class="branch-line collie active" marker-end="url(#arrow-collie)" />
      
      <path id="path-lap" d="M 150 0 C 150 24, 250 16, 250 42" class="branch-line lap active" marker-end="url(#arrow-lap)" />
    </svg>

    
    <div class="breeds-grid">
      
      
      <div class="breed-card husky active" data-breed="husky">
        <span class="breed-icon">🐕</span>
        <div class="breed-name">Sled Dog</div>
        <div class="breed-sub">Husky</div>
        <div class="badge badge-husky">
          Thick warm coat<br>High endurance
        </div>
      </div>

      
      <div class="breed-card collie active" data-breed="collie">
        <span class="breed-icon">🐕‍🦺</span>
        <div class="breed-name">Herding Dog</div>
        <div class="breed-sub">Border Collie</div>
        <div class="badge badge-collie">
          High focus<br>Fast runner
        </div>
      </div>

      
      <div class="breed-card lap active" data-breed="lap">
        <span class="breed-icon">🐶</span>
        <div class="breed-name">Lap Dog</div>
        <div class="breed-sub">Pug / Chihuahua</div>
        <div class="badge badge-lap">
          Small size<br>Gentle companion
        </div>
      </div>

    </div>

  </div>

  <div class="instruction">
    <span>✦</span> Tap any dog to highlight its selective branch
  </div>

  <script>
    const cards = document.querySelectorAll('.breed-card');
    const lines = {
      husky: document.getElementById('path-husky'),
      collie: document.getElementById('path-collie'),
      lap: document.getElementById('path-lap')
    };
    const markers = {
      husky: document.querySelector('.arrow-marker.husky'),
      collie: document.querySelector('.arrow-marker.collie'),
      lap: document.querySelector('.arrow-marker.lap')
    };
    const ancestor = document.getElementById('ancestor');

    let activeSelection = null;

    function selectBreed(breed) {
      if (activeSelection === breed) {
        // Reset to all active
        activeSelection = null;
        cards.forEach(c => c.classList.add('active'));
        Object.values(lines).forEach(l => l.classList.add('active'));
        Object.values(markers).forEach(m => m.classList.add('active'));
        return;
      }

      activeSelection = breed;
      cards.forEach(c => {
        if (c.dataset.breed === breed) {
          c.classList.add('active');
        } else {
          c.classList.remove('active');
        }
      });

      Object.keys(lines).forEach(k => {
        if (k === breed) {
          lines[k].classList.add('active');
          markers[k].classList.add('active');
        } else {
          lines[k].classList.remove('active');
          markers[k].classList.remove('active');
        }
      });
    }

    cards.forEach(card => {
      card.addEventListener('click', () => {
        selectBreed(card.dataset.breed);
      });
    });

    ancestor.addEventListener('click', () => {
      // Show all branches
      activeSelection = null;
      cards.forEach(c => c.classList.add('active'));
      Object.values(lines).forEach(l => l.classList.add('active'));
      Object.values(markers).forEach(m => m.classList.add('active'));
    });
  </script>
</body>
</html>

Could a farmer turn a wild wolf into a tiny poodle in just one summer?

Selective breeding is not magic — it cannot change an animal overnight.

Because babies get a mix of traits from both parents, humans must repeat the selection process over many **generations** to make lasting changes.

science

What Is Artificial Selection or Selective Breeding?. Define selective breeding as humans choosing parent organisms with desired traits to reproduce.

Inheritance, Variation and Selective Breeding (KS2 Science / Year 6)

Selective Breeding of Plants (KS2 Science / Year 5-6)

Artificial Selection and Domestication: How Humans Shape Traits

When teaching this objective to Key Stage 2 (Years 5–6), anchor the concept in concrete, familiar examples such as pets (dog breeds) and supermarket produce (carrots, apples, brassicas) before moving to theoretical mechanisms. Emphasise the active role of humans in choosing specific characteristics, contrasting this clearly with natural selection where nature/environment dictates survival. Use structured multi-step graphic organisers to reinforce that selection is an ongoing process across generations, not an instantaneous event.

What Is Artificial Selection or Selective Breeding?

What Is Selective Breeding?

From Wild Grass to Sweet Corn

Choosing Traits in Animals